What's the difference in talk time on a 1500mAh, 2000mAh & 2500mAh?

Intell

macrumors P6
Jan 24, 2010
18,883
372
Inside
Well, the iPhone 4S has a 1430mAh battery. So any of those cases would double the talk time.
 

B2FiNiTY

macrumors member
Nov 28, 2011
58
0
Due to the efficiency of those products and the phone running at the same time as charging, you'll need around 2800mAh to fully charge your iPhone from 0-100%.
 

takeshi74

macrumors 601
Feb 9, 2011
4,972
68
Click through and read the details on the Morphie site. Example:
http://www.mophie.com/mophie-juice-pack-air-iPhone-4-4s-battery-case-p/1145_jpa-ip4-blk.htm
Featuring Apple's coveted "Works with iPhone" certification, this innovative smart battery case adds up to an additional six hours of talk time (up to 12 on 2G) or Web browsing to your iPhone 4/4S.
Also listed in the specs section:
Additional Battery Hours:

iPhone 4:
Standby Time: Up to 270 hours
Talk Time: Up to 6 hours on 3G | Up to 12 hours on 2G
Repeat for their other products as desired.