This App is only for ACCU-24 Batterien & Systeme GmbH
Easy to use tool for monitoring your lithium battery !  
Event recorder and notification reminder  
The phone requires bluetooth4.0 with BLE(bluetooth low energy) functions.  
ios 11.0 or later 

The APP only can contact with one battery at one time. 

If you want to connect this battery with another mobile phone, pls exit this app program from the first mobile phone.  
The iPhone system is an open platform. Not every smartphone manufacturer complies and some have customized features.  
So the APP may not work on all smartphones due to compatible issue.