Nokia Lumia 720 is a better option when compared to iPhone 4S. The Lumia 720 gets a bigger 4.3 inch touchscreen with 480×800 पिक्सल. The use has been eased with the introduction of Windows 8 mobile to the phone. It gets a bigger battery, higher camera resolutions and a better price tag for the overall practicality of the phone. The iPhone wins when it comes to screen resolution and full HD recording and playback option.
It depends on your preference towards the Operating system. I suggest you to try both phones before purchasing. Even though I use an Android phone, I admire my friend’s Lumia 730 as it’s display is awesome with perfect viewing angles, no lags and a good design and build quality. Also iPhone 4s is a bit too outdated now. I vote for Lumia 730.