I haven't had any apps custom designed for me, but I have bought two preexisting apps from developers on Flippa. The first one cost me $19 and it's a Match 3 game called Animal Bubble. It's cute, but a little buggy, but what do you expect for $19? The second app cost me $50 and it's an endless runner called Run Weed Man Run. I really wanted it because it fit in with the niche of one of my very first sites.
They're both free on Google Play if anybody wants to try them out and let me know what they think.
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