The app needs to be fixed, hopefully in the near future... my workaround is to close the app and reopen it, sometimes it works at second attempt, sometimes it fails again while loading the game. Even when it works, navigation through journal is tricky and the chat is laggy. I would only recommend to use it IRL games with other alternative sources to get the information. The Table on Tablet Support is not related to the app, you have to use Chrome or Firefox to access Roll20 on your device. At the last game I've run one of my players was able to play the session just using his Android tablet and I've used my iPad to show maps many times at other games.