How can I adjust my code so that the value that I print with my BLE device does not get chopped up when I receive it on an app?
how can I adjust my code to make sure it does not send the result chopped up but instead sends it's complete value?


The BLE device uses a package approach and the print member functions only support strings (char vectors and Arduino String). Construct the message as a String:

double lat = gps.location.lat();
double lng = gps.location.lng();
String msg = String(lat, 8) + String(", ") + String(lng, 8);
BTLEserial.print(msg); 


Cheers!