You’ve hit a couple of issues that are under active development. The logging is the last major feature that hasn’t been implemented yet. Sorry about that, please watch the blog for new releases (including a release to the Google Play Store).
The only concern you’ve raised that seems out of the ordinary is the update rate – you should be seeing the meter update substantially faster than 1Hz. Can you send a screenshot of the main text page to make sure your settings are correct? If everything is set to auto you should be seeing updates at almost 4Hz.