There are several factors affecting the quality of connection between the device and the app, as well as the performance of the app.
1) The charge level of the training device and the smartphone
2) The amount of free space on the phone
apps work slower if the storage is almost completely full
3) Reset the Bluetooth connection
How to reset an incorrectly established connection and establish the connection again?
- Go to your phone settings and find the Bluetooth settings section
- Find the remembered training device your smartphone has connected with, unpair (disconnect) the devices (the button may be also called “forget” – the name will differ depending on the phone type and model
iOS: Click the information icon , and then disconnect the pair
- To make the connection solid and the amount of the sent data optimal, it’s important to connect with the device only from the app level
4) The phone’s operating system
it should be updated