Don't release it under the GPL. Due to Apple app store restrictions, GPL'ed apps cannot be distributed that way. It's probably best to pick a BSD or Apache style license.
Being an app developer is frustrating even on Android. Getting publicity for your app is difficult. Margins are thinner than you think because prices are low and your time isn't free.
My feeling is that the market is currently oversupplied with app developers and it needs to cool down. More posts like this would be good to counter the gold rush mentality of the past few years. There just isn't that much money in apps, unless you own the App store.
I also don't see learning Objective C as being that useful, unless you want to continue being an iOS developer... which it seems that you don't. Remember, your main career goal as a developer is not to paint yourself into a corner.
Being an app developer is frustrating even on Android. Getting publicity for your app is difficult. Margins are thinner than you think because prices are low and your time isn't free.
My feeling is that the market is currently oversupplied with app developers and it needs to cool down. More posts like this would be good to counter the gold rush mentality of the past few years. There just isn't that much money in apps, unless you own the App store.
I also don't see learning Objective C as being that useful, unless you want to continue being an iOS developer... which it seems that you don't. Remember, your main career goal as a developer is not to paint yourself into a corner.