This guide is using a Bosch PLR50C as an example, but the same also applies similary to any other device.
First, we should make sure that no other app is connected to the laser-distance meter. Since the distance meter can only be connected to one application, an existing connection will block any further connection requests. On most laser-distance meters, a Bluetooth icon indicates whether the device is currently connected or not.
If you have another app running in the background (e.g. the vendor's app), it may continuously
try to reconnect to the distance meter. Even when this is happening infrequently, like every
couple of minutes, it may disturb a reliable connection process.
In this case, you should stop the other app by
opening the Android settings and choosing 'Apps' →
Open the ImageMeter settings on the main screen. Scroll down to the Bluetooth section. Select the first item 'Laser distance meter'. A screen appears that lists all known Bluetooth devices. If your distance meter is in this list, select it. If it is not in the list, turn on Bluetooth on the distance meter and click on 'Start Bluetooth Device Scan'. Now your distance meter should appear in the list. When you select it, it is automatically paired with your Android device.
On some devices, the distance meter name does not show (i.e., only its Bluetooth address appears). In this case, you should pair the devices manually in the Android Bluetooth settings. It will then appear in the ImageMeter settings as a known device.
In the ImageMeter settings, you can also choose the Bluetooth protocol manually. However, usually, it is best to keep this at 'automatic'.
Now, back on the main screen of ImageMeter, click on the Bluetooth icon. It will start to blink, indicating that it is now trying to connect to the distance meter. If this is the first connection between the devices, ImageMeter will start a pairing request. When the connection is successfully established, the icon will turn blue and we are ready to go. If it does not work, check again that there is no other app blocking the connection and that the correct device was selected in the settings. In very rare cases, you may need to restart the distance meter or your Android device.
With the distance meter connected to ImageMeter (blue Bluetooth icon), open an image to enter the editor. Values transmitted over Bluetooth are always copied to the active measure. Hence, either draw a new measure or select an existing measure. When you now carry out a measurement on the distance meter, it will appear automatically at the selected measure. On some devices (e.g. Leica D3aBT), you have to explicitly press the Bluetooth button on the laser meter to transmit the value.
Depending on the distance meter model, and the mode it operates in, it will not only transmit lengths, but also angles or areas. If these are transmitted, they can also be received by ImageMeter. Which value will be received depends on the measure selected in ImageMeter. For example, a device might always transmit a length and the angle, at which it was taken, together. When a length measure is active in ImageMeter, the length part will be received, and when an angle measure is active, the angle will be received, respectively.
A special case is the reference object, as it needs two measurements: one for its horizontal side and one for the vertical side length. The first measurement taken will be copied to the horizontal side and the following measurement to the vertical side.