[trevmckendrick]

All of the above. I bought quite a few of them.

It doesn't take too long to get a feel for how good an app is.

[trevorcreech]

But how did you know they were making money?

[monkey_slap]

AppAnnie (http://www.appannie.com/) gives some good insight in how well apps are doing.

[trevmckendrick]

Gross rank for apps reveals a lot. Any top 25 app by gross rank is doing well by "niche" standards.

[pc86]

Doesn't Apple only let those who have purchased write a review? If so, the gross number of reviews may give some idea of how many have purchased the app (ignoring price fluctuations, etc)

[trevmckendrick]

Some developers have told me this is a good rule of thumb, but for others it's way off. Mine # of reviews is not really indicative of how many downloads.

[callmeed]

From what I've read it's:

(# reviews * 30)

[GotAnyMegadeth]

My apps are more like (n * 100). But that is on Android...