IPhone 4S won't take high quality video?

I bought my wife an iPhone 4S and it did fine for a long time. In the last 6 months, however, it started this new thing where it refused to take videos in high quality. It takes high quality photos, but on video it looks like you took the video with an old low-quality cellphone. The quality makes 240p on Youtube look like high quality. The sound is also not especially great but isn't the main issue. What would cause this? She updated her phone to ios6 after this problem occurred and doing this update had no affect on the quality of her videos. There's another strange aspect to this problem. When I send high quality videos from my iPhone 4 to her 4S, the videos get messed up on her phone and put into this extreme low quality when played back, despite the fact that they look great on my phone and when I send them to Facebook and YouTube. Any tips on what is wrong and how we can fix it?

It shouldn't take long to realize iPhone is terrible. The Galaxy phones in every version have beaten this phone so many times it's just stupid to go with iPhone in general. My advice, buy a better phone. Get the Galaxy s4 with 13 megapixel camera and huge display. Those two things alone beat iPhone.