I saw this on Medscape site. It is apparently better than AliveCor but I could not find the app on Google Play. Maybe it has not been released yet.
Below is the conclusion reached in the Medscape article:
In this novel analysis of 219 pulse waveform recordings, we show that we have developed an app capable of transforming a smartphone into a device capable of screening for AF in real-time in a cohort with a diverse array of benign arrhythmias likely to cause false positives using preexisting systems. We have also demonstrated that our app running on "out-of-the-box" hardware is highly acceptable to older users. To our knowledge, no existing smartphone-based app for AF detection uses the combination of pattern recognition, computational speed, and robust noise cancellation routines that our app employs while requiring no additional hardware (i.e., special phone case or Bluetooth sensor). On this basis, we believe PULSE-SMART represents an exciting new platform to enhance AF screening. Plans for future development include an open trial and formative qualitative work with older users so that the app and its interfaces meet their needs.