Table of Contents

• What is iPad RTK surveying?

• Challenges of field surveying and conventional methods

• Why no special skills are required

• How RTK achieves centimeter-level positioning

• Benefits of using an iPad

• Use cases for iPad RTK surveying

• Simple surveying with LRTK

• FAQ

What is iPad RTK surveying?

In recent years, a new style called "iPad RTK surveying" has attracted attention in construction and surveying fields. This approach combines everyday devices like the iPad with high-precision positioning technology known as RTK (Real Time Kinematic), enabling anyone to easily perform centimeter-level surveying. Tasks that previously required specialized surveying equipment and advanced skills for setting out positions are increasingly achievable with a single tablet at hand. This trend is greatly accelerating the digitization and efficiency of field work and is expected to be a transformative change that overturns conventional wisdom.

The basic mechanism of iPad RTK surveying is to connect a high-precision GNSS receiver to a tablet device (iPad) and perform positioning in real time using correction information. This can reduce errors that would be several meters with ordinary GPS down to several centimeters. Field personnel can operate a dedicated app on the iPad and obtain accurate position coordinates simply by pressing a button at the point to be measured. All difficult operations and calculations are handled automatically by the app, so no specialized surveying knowledge is required to use it.

Challenges of field surveying and conventional methods

Conventional surveying work required professional surveyors and expensive surveying instruments (such as total stations and GNSS survey instruments). To carry out accurate positioning and leveling on site, experienced personnel needed to set up instruments, perform observations, and compute and adjust the acquired data. These traditional methods had several challenges.

• Human resources and cost: Because specialized technicians must be arranged, labor costs and outsourcing fees tend to be high. In addition, the high-precision surveying instruments themselves are expensive, and introducing even one unit to a site represented a significant investment.

• Time and effort: Many steps are required from preparation to execution and data organization, so the work takes time. When there are many measurement points or when repeated measurements are needed, calling in experts each time is inefficient.

• High learning barrier: Accurate surveying requires specialized skills such as instrument handling and knowledge of coordinate systems. It is not a task that newcomers or engineers from other fields can immediately take on, and training personnel also takes time.

Against this backdrop, demand grew for "a way to survey more easily and quickly." iPad RTK surveying emerged precisely to solve these problems. By leveraging tablet devices that people are accustomed to using daily, non-specialist staff can participate in field measurements. Combining high-precision positioning technology with an intuitive app interface significantly lowers the barrier to surveying and creates an environment where more people can perform surveying tasks.

Why no special skills are required

As the catchphrase "high-precision measurements without special skills" suggests, the ease of operation is a major attraction of iPad RTK surveying. Why can it be used effectively without advanced surveying skills? Here are the reasons.

First, an intuitive user interface. Surveying apps running on the iPad operate similarly to common map or camera apps. Tap a button on the screen at the point you want to measure, and the app records coordinate data such as latitude, longitude, and elevation. The app automatically performs necessary coordinate system conversions and elevation corrections (such as geoid height adjustments) and displays the results, so users do not need to be concerned with difficult numerical calculations.

Next, all-in-one surveying functions. iPad RTK solutions integrate a variety of functions. In addition to single-point position measurements, they can capture continuous point clouds, calculate areas and distances, and even output positions for setting out according to design drawings—all with a single device. For example, if you need to place a stake at a fixed offset distance from a reference point, the app can display the target point and guide you to move to that location and perform positioning and marking. These operations proceed with guide messages and simple button presses, so users can operate without detailed knowledge of technical terms.

Furthermore, simplified preparation is a major point. With dedicated instruments, setup, calibration, and establishing reference points took time. With iPad RTK surveying, you can attach the receiver to the device and power it on to start positioning in a short time. The reduced complexity of preparation makes it easy to "measure whenever you think of it," which is a great advantage on site.

For these reasons, people who have not received special training can achieve high-precision measurements with iPad RTK surveying. Those familiar with smartphones or tablets can become productive in field surveying tasks after learning only a few operations.

How RTK achieves centimeter-level positioning

The core technology of iPad RTK surveying is a high-precision positioning method called RTK. RTK (real-time kinematic) dramatically improves positioning accuracy by applying real-time corrections to satellite positioning such as GPS. As a result, GNSS positioning, which used to have errors of several meters, can be improved to centimeter-level accuracy.

RTK basically works by having both a base receiver at a reference point and a rover receiver on the moving unit receive satellite signals simultaneously, and correcting error factors by comparing the data from the two. Previously, it was necessary to install a dedicated base station or receive correction information (RTK correction data) via cellular networks. Recently in Japan, the Quasi-Zenith Satellite System "Michibiki" provides a centimeter-level positioning augmentation service (CLAS), and compatible receivers can obtain high-precision correction information directly from satellites without an internet connection. Therefore, centimeter accuracy can be maintained even in mountainous areas or places without network coverage.

The small RTK-GNSS receivers that connect to an iPad support CLAS and network-based correction services, enabling real-time acquisition of corrected position information on site. For example, when measuring the coordinates of a point, the app displays high-precision latitude, longitude, and elevation with corrections applied in real time. Repeated measurements and averaging can further improve accuracy. The resulting positions typically have errors within a few centimeters, providing sufficient precision for construction site management and as-built measurements.

Benefits of using an iPad

The benefits that iPad RTK surveying brings to the field go beyond simply enabling high-precision positioning. By leveraging tablet-specific features, it offers various advantages not found in conventional surveying.

• Portability and responsiveness: With an iPad and a pocket-sized receiver, there is no need to carry heavy tripods or bulky equipment. You can move around the site and take measurements on the spot, allowing flexible workflows where surveying can be done between other tasks.

• Real-time sharing: Tablets have communication capabilities, so acquired positioning data and measurement results can be uploaded to the cloud immediately. Staff in the office can share information in real time, enabling progress reporting and data verification and facilitating smooth collaboration across site and office.

• Rich sensor utilization: Models like the iPad Pro include LiDAR scanners and high-performance cameras. Combined with RTK’s high-precision position information, you can obtain 3D point cloud data with high accuracy. Scanning structures for precise dimensions or creating digital terrain models can be handled with just a tablet.

• Intuitive visualization with AR: Augmented reality (AR) features can overlay design drawings and measurement points onto the actual scene through the tablet screen. This lets you confirm visually where to place stakes or where designed structures will sit in the field by overlaying them on the camera image. Even without interpreting complex drawings, users can intuitively understand positions on site, reducing communication loss and mistakes.

• Centralized digital records: Instead of relying on paper field notebooks or memos, all surveying data is stored digitally. Entries are linked with date/time, point names, and photo notes, making later review easy and reducing the risk of data loss or transcription errors. Once uploaded to the cloud, multiple people can view and edit the data simultaneously, improving information sharing.

By using an iPad in this way, the efficiency and precision of field surveying—and the scope of information use—expand dramatically. The iPad functions not just as a measuring tool but as an on-site information hub, which is the key to this new surveying style.

Use cases for iPad RTK surveying

So, in what kinds of sites is iPad RTK surveying useful? Here are some expected use cases.

• Stakeout and setting out on construction sites: It is useful for accurately marking foundation positions and the locations for installing structures. Tasks that used to be done by a surveyor measuring angles and distances with a total station can now be done by a worker carrying an iPad, moving to the indicated point, and marking it. With AR display, you can overlay virtual stakes or lines from the design data to visually check for positional discrepancies while working.

• Land surveys and as-built management: It is effective for surveying terrain before and after earthworks and for managing as-built conditions. On large sites, workers can walk around and measure heights and positions at required points, then immediately share the data to the cloud. Because terrain changes daily during earthworks, iPad RTK surveying enables same-day acquisition of current 3D data and quick comparison with design models, shortening the PDCA cycle.

• Infrastructure maintenance and management: High-precision positioning is powerful for recording location information during inspections of roads, water and sewer systems, and power lines. While circulating inspection points, capturing photos with the iPad together with accurate coordinates allows precise identification of problem locations on a map later. Information that used to be managed in paper ledgers with descriptions like "x meters from y" can be centrally managed on digital maps, improving maintenance efficiency.

• Situational assessment at disaster sites: In the aftermath of earthquakes or landslides, it is essential to quickly survey and record damage. Staff who reach the site can use iPad RTK surveying to measure terrain changes and the positions of damaged objects without waiting for specialized survey teams. Ground-level measurements can capture fine details that drone or aerial imagery might miss, making this method valuable for initial response information gathering.

Beyond these examples, iPad RTK surveying excels in any situation where accurate position information is required, such as field management in agriculture or current-condition surveys for urban planning. The key point is that non-specialists can use it directly at the frontline. Because situational assessment, recording, and reporting can all be completed on site, this approach has the potential to change how work is conducted.

Simple surveying with LRTK

One example of a product that implements the iPad RTK surveying concept described so far is LRTK. LRTK is a compact RTK-GNSS receiver used by attaching it to an iPhone or iPad, turning a typical smartphone into a centimeter-level surveying device. Its characteristics emphasize the "ease of use" and "practicality" needed on site.

The LRTK unit is compact enough to fit in a pocket and can be attached to a device with a dedicated attachment in one touch. It weighs approximately 125 g and is very lightweight, so it does not burden transport. Because it has an internal battery, it can maintain stable positioning accuracy even during long measurement sessions on site.

Start the dedicated app and positioning is possible immediately without complicated settings. At the point you want to measure, hold up the iPad and press a button to obtain and save high-precision position information in real time. Measured data can be uploaded to the cloud with a single tap and automatically plotted on the company’s shared web map, eliminating the hassle of transferring data via USB back at the office.

By using LRTK, you can establish a one-device-per-person system in which each worker can perform surveying on their own device without special skills. This allows small measurements on site to be completed by the workers themselves without waiting. For example, you can verify buried piping locations or immediately measure earth volumes created by heavy machinery; being able to measure and obtain results on the spot dramatically improves work efficiency.

As a simple surveying solution, LRTK supports a productivity revolution on site. From an era in which expensive equipment was handled only by specialists to an era in which affordable devices are carried and used by everyone—LRTK embodies the idea of iPad RTK surveying that changes the field.

FAQ

Q: What do I need to start iPad RTK surveying?

A: What you need is a tablet device such as an iPad, an RTK-capable GNSS receiver, and a dedicated surveying app. Specifically, prepare a small RTK receiver that can be attached to an iPad (for example, a device like LRTK) and install that device’s dedicated app. After performing initial setup in an internet environment, you can perform centimeter-level accuracy (half-inch accuracy) surveying in real time on site. If you use a receiver compatible with satellite augmentation services such as Michibiki (QZSS) CLAS, you can achieve high-precision positioning even in mountainous areas without a network connection.

Q: Can I really use it without surveying expertise?

A: Yes, you can. Apps for iPad RTK surveying are designed for intuitive operation, and map displays and measurement procedures are clearly guided. Difficult coordinate calculations and elevation corrections are automated, so users simply follow on-screen instructions and press buttons to obtain necessary data. Anyone who can operate common smartphone apps can master the basics of high-precision surveying with a short training session.

Q: Why do I need an RTK receiver instead of the iPad’s built-in GPS?

A: The GPS built into iPads and smartphones has an accuracy on the order of several meters. That is sufficient for showing your current location on a map app but cannot provide the centimeter-level accuracy required for surveying. RTK receivers receive multi-frequency GNSS signals and apply correction information to compute high-precision positions. In short, an RTK receiver upgrades a phone’s GPS to professional-grade performance, so dedicated RTK receivers are essential for true surveying.

Q: Is the accuracy and reliability sufficient compared to conventional surveying instruments?

A: The accuracy obtainable with iPad RTK surveying is practically sufficient for many applications. In open, flat environments with good satellite visibility, horizontal and vertical errors typically stay under 2–3 centimeters (0.8–1.2 in). Under favorable conditions, accuracy can be even better. This level is comparable to general GNSS survey instruments and is suitable for tasks such as residential land development and positioning of structures. However, in cases requiring millimeter-level precision, it is recommended to use conventional optical surveying instruments (such as total stations) in combination as appropriate.

Q: Can it be used in areas with poor radio or communication environments?

A: RTK surveying fundamentally relies on receiving satellite signals, so positioning accuracy can degrade in areas where the sky is obstructed, such as amid tall, densely packed buildings or within forests. However, receivers that support Michibiki’s CLAS can obtain correction information directly from satellites without relying on mobile communication networks, allowing positioning to continue in mountainous or out-of-coverage areas. Devices like LRTK are also designed with high-performance antennas to improve satellite signal reception sensitivity. Although accuracy may decrease somewhat depending on site conditions, stable high-precision performance can be maintained in open areas.