How long does it take to approve an iphone app?

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#1 - July the 15th, the day that we submitted our app to the AppStore. The few impressions shown on the screen are our own ad requests since we ran the app a couple of times. Then the silence was on for a couple of days until last night when I noticed a small “peak” #2. Seems that Apple was testing my app (they work Sundays?). Today we don’t have any impressions. Judging from the last review process, I believe that the app will be approved today or tomorrow at latest. The funny thing is that the “peak” shows only 7 ad requests. Our app has about 5-6 screens with ads, does this mean that they went through the each screen only once? ![]()
UPDATE:
Today I got another 5 ad impressions, seems that Apple’s still reviewing our app!
UPDATE #2 (07/30)
The app finally got approved today but the release date on AppStore is July the 20th! I believe there was something wrong with iTunesConnect or AppStore review process since there are a few more developers contacted me with the similar problem. So, just like our previous app - this one got reviewed 4 days after submission (and one would expect to be released the next day which is exactly the July 20th what currently stands as release date) but the some kind of problem arised so they delayed the releases for about 10 days.