Google Play vs Apple's App Store?

Hey everyone!
I’d like to know if it’s worth dropping 100€ on the Apple Developer Program or should I rather spend a 1/4 of that money for a one-time-fee for Google’s registration fee. Will I see that money coming back anytime soon? Is it hard to make money off these mobile app stores and do I need to invest in marketing? Thanks in advance!

Well for start Google Play is best option when you have limited budget, since is a 1-time fee I don’t have to worry about license expiration and can upload as many apps as I wan’t as long as it follows the dev guide.

After my app is popular enough making me at least $3 a day I release to apple, then my app on Play Store support App Store license while in App Store make my revenue. Later on this won’t be necessary but you get the point.

Marketing is always necessary, much better if is paid, but don’t waste money if you don’t need to. Use free resources like Facebook, Twitter, Blogs, Forums, friends of Friends of Friends and so on…

Good Luck,