- there are official apps also that you can download. Good idea to set up a new google account with Thailand as your location as some apps only available from thai play store.
- the 80,000 bht should read 800,000 bht - it looks like they are talking about a combination of income and savings - the total over 12 months should not be less than 800,000 bht. Best to check this sort of stuff on an official thai immigration website.