Samsung Galaxy S2 works on 2G, 3G network with GPRS/ EDGE band, also has Wi-Fi 802.11 a/b/g/n, dual-band, DLNA, Wi-Fi Direct, Wi-Fi hotspot features. For data sharing it has bluetooth and Wi-Fi direct to exchange data with other devices, microUSB v2.0 (MHL), USB On-the-go to share data with computer. It comes in 16GB/32GB internal memory and external memory can be extend up to 32GB, 1 GB RAM and Dual-core 1.2 GHz Cortex-A9 makes this phone faster, and a better phone for gamers. This phones has Radio, GPS , Java and other features in extras which makes this phone better then galaxy S. Sounds are good and 3.5mm jack earphone make it's sound more better in earphones.
The phone has just got android 4.0 (Ice cream Sandwich) update , it can be updated via Samsung PC Suite Kies.