Review on CTEK (40-149) CTX Battery Sense - Smart Battery Monitoring via Mobile Phone by Mark Tarnowski

I have 2 CTEK battery sensors in a car to monitor my high quality car radio. One for the main engine battery and one to control my auxiliary shuriken battery in the trunk which powers my car stereo. I've read the complaints and encountered many of the same problems as you. If it works it's great, if it doesn't work it sucks. After experimenting with the various options and fixes recommended by the company, I found that Battery Sense can lose connection when your phone receives an automatic update or another app receives an update. What I did was just restart my phone within bluetooth range. After the reboot, go to the Bluetooth settings on your phone, turn Bluetooth off and on again. It should be re-synced and updated with the current time. If it gets stuck again, repeat the process. The same happens when you turn off or replace the battery. This is where I figured that simply closing and reopening the application would allow an update on how wrong I was. Hope that helps.