I am not sure of the resolution...This is no doubt due to resolution which I am not sure I can change?
I thought I gave you some reasonable options:
1. Continue to send videos via email - this will allow you to transfer a larger video than MMS
2. Use any file hosting service that supports cross-platform use (I haven't looked to see if the popular ones support iOS, but I'm sure you can find one)
3. Regarding your last question - it is possible to change the video resolution that you use when recording. (I'm not running the stock ROM at the moment, or I'd provide you with specific steps/screenshots.) If I remember correctly, once you've switched to video mode in the stock camera app, press the gear symbol to bring up the settings, then scroll down the list to Resolution, pick that item, and it should show you all of the available capture resolutions: the smaller the resolution, the longer you can record video (and still end up with a comparably-sized file).
Edit: I just checked and both Box and SugarSync offer iOS clients - so you can check with your daughters and see which they prefer; most of the file hosting services offer 5GB free, so that should be plenty for common sharing of pictures/videos.
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