Steem on mobile is rough. With a tight budget, I recommend always keeping your eye open for people who have crashed laptops laying around. You would be surprised how cheaply some people will let them go, because they are not willing to fix them,(or don't know how) and taking them to a repair shop can be damn near as pricey as buying a new one oftentimes. Many get new , and have junkers laying around. (at least around here.)

If you manage to find one, you could set up a Linux OS pretty easily (and Linux is free opensource software, unlike Windows which you would have to buy or pirate.), and run chrome, set up keychain, boom you have a steem machine. (Linux is also not very hard to operate. You just need to know some update commands, and a few others, which you can save in a note and paste them into the terminal.)

If you happen to get one and need any help, hit me up and I'll be happy to offer some guidance if needed.