Using Blockfolio on IOS.
So far had no any issues. I know that for some new coins it can go crazy and shows some unreal amounts, but it is unknown if its blockfolio issue or exchange provides wrong data.

For me it do what it has to - tracks prices and shows PnL. But alerts doesnt seem to work fine, at least in my particular case - I tried to set it for a few times but for every coin i received notice with 10 minutes delay, that makes it pointless.