I have 2 accounts through 2 different companies. Both require me to have notifications on so I know when an item has been assigned to me. That being said, I can not find a way to have 2 accounts on the 1 app for android. This would be a great addition. Make it like slack or google, where you only work in 1 at a time but the others run in the background still signed in.
If you currently have 2 accounts, you can merge them following these steps: https://asana.com/guide/help/fundamentals/accounts#gl-merge-accounts
Hope this helps, but let us know if you have any follow-up questions!