I got the average by subtracting all the time zone numbers and the average is around 34,000. I divided 340,945,524 with 34,000 and got 10027.8 which I rounded up and got 10028. After that you divide by 60 and you should get 167. That means that we are only 167 hours away from the 25th billion download. There are 24 hours in a day so you divide 167 by 24 and should get 6.99999 and on. the download was around 24,658,000,000, and it started around 6:27 pm. I rounded up on 6.99999 and just made it 7 so I would start to download around 7 days which is a week so start downloading at 6:27 next week. The date would be February 31 when it hits the 25th billion download.
http://www.google.com/url?sa=t&rct=j&q=dan%20meyer%2025%20billion%20app%20download&source=web&cd=1&cad=rja&uact=8&ved=0CCAQFjAA&url=http%3A%2F%2Fthreeacts.mrmeyer.com%2F25billionapps%2F&ei=p2vbVJX8DtGeyASE2ILwCg&usg=AFQjCNFChZQFDq5CT_8wG3wiM_9PETzcyA&bvm=bv.85761416,d.aWw