Provide more details and perhaps we'll get some context.
OK I will explain in detail what I noticed starting at the beginning. Everything I describe applies to the U.S. App Store.
1. On May 17th, MoneyCounter appeared out of nowhere somewhere around the top 10 paid Finance apps (don't remember the exact position). I say "out of nowhere" because although May 17th was its first day in the app store, the app's release date is set to April 11th, which means it did not appear in any of the new releases lists (either in iTunes or the App Store app), which is usually key for a new app to get noticed.
2. Once I noticed #1, I looked at the app to see if it was awesome enough on its own to get noticed and move up to a top spot. It's clearly not. I know "bad" apps often get ranked in other categories, but Finance is far less fickle. I haven't seen the app advertised anywhere, either.
3. It has no reviews that appear in iTunes and 2 reviews (for a total of 2.5 stars) that appear in the App Store (these are both U.S.). My app was #1 in Finance for a couple weeks recently, which means it should get at least 250+ downloads a day which inevitably leads to at least a dozen or so reviews per week.
3. Given 1, 2, and 3, the app has still been moving UP the top paid list. It was as high as #1 on May 23, and seems to have settled on #2. Again, this wouldn't be weird for an app to move up the list once it appears in the top 20 or so, but the app is not appealing to the average user at all. Maybe it is useful to a small number of people, but not enough to make it as popular as it appears to be.
4. The price changes I mentioned earlier seem to correspond with the app's ranking changes, but that could be coincidence.
5. The guy's other app is a $19.99 fart machine called yFart. On May 24th he also lowered the price of that app to $4.99 briefly before raising it again to $19.99. All three written reviews for this app call it a "scam," although those users sound a little confused.
It wasn't my intention to make a big deal about this, I just thought it seemed weird and figured other people would too, but I guess it's not as obvious to someone who isn't obsessed with the Finance category.