If it's making a few hundred $ a day, that's not bad going, that's a few thousand every 10 days. You should be able to take someone on and pay them to maintain and improve the software, surely?
We're a bit inexperienced when it comes to hiring people - I wouldn't expect to find anyone reasonably good with say $1k for a single week of work? The apps definitely don't require a full time person for the next six months - maybe a proper week of worth every month would be appropriate.