Yet another 18650 battery build.

[parabellum]

With BMS you don't know what is going on until your pack is not working. I don't trust BMS boards made in China and I'm definitely not paranoid if comes to Li-ion batteries.

Except it is BT BMS that has a big display and BT connection to your Android to show you more then your testers will ever show.

 

[llile]

smartBMS APP can only suitable for Android 4.3 and supports Android device only with bluetooth version 4.0 or higher ,try this Bluetooth Android APP-2.1.1012, see if it can work?

This app worked for me, although, as I expected, the security settings in Andriod were not happy about an app that didn't come from Google Play. I do not believe it is actually any danger.

 

[Ecyclist]

With BMS you don't know what is going on until your pack is not working. I don't trust BMS boards made in China and I'm definitely not paranoid if comes to Li-ion batteries.

Except it is BT BMS that has a big display and BT connection to your Android to show you more then your testers will ever show.

It's a BMS and costs $150. Is Neptune 15 really worth that much? Not to me.
I just use loggers to tell if one of groups is low. Everything else I get from VESC via BT on my phone. Most of the time I don't bother with keeping track of all that fluff and just use CatEye Strada for speed.
VESC 4.12 controller that runs my motor and can do tons of other stuff is under $100. VESC TOOL app can provide all data I need and is $1.99. You can see it here: https://play.google.com/store/apps/details?id=vedder.vesctool
Something to consider.