I'm seeing a very similar issue with my only (free, no ads) app which generates 0-5 daily downloads on average. There are mysterious download spikes all the way to 500 on a single day - all those downloads happened in Germany though (my app supports EN and DE). Every such spike is a clean n*100 downloads.
Apple, I think you really need to get to the bottom of this! Evidently there are more apps out there affected by manipulated download spikes.
Topic:
App Store Distribution & Marketing
SubTopic:
General
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