As for differences from the Verizon version, AT&T doesn't stray too far. You'll find a few of the carrier's custom services like AT&T Code Scanner, AT&T Family Map, AT&T Navigator, Live TV, and the MyAT&T account portal. You'll also find Media Discovery, Office Suite, Yellow Pages Mobile, and Amazon's Kindle app. Gamers get seven installed titles (Asphalt 6 Navigator, Crash Bandicoot, Dungeon Defenders: Second Wave, Madden NFL 11, Star Battalion, Tower Bloxx: My City, and The Sims 3), along with access to many more games for download.
We tested the quad-band (GSM 850/900/1800/1900) Sony Ericsson Xperia Play 4G in San Francisco using AT&T service. Call quality was generally agreeable with clear audio, little static or interference, and loud volume. We didn't notice the fuzzy voice quality that we found on the Verizon phone, but callers sounded a tad robotic.
On their end, callers said we sounded quite good. Here again, we didn't hear the fuzzy effect that we encountered on the Verizon phone. In fact, some of our friends couldn't tell that we were using a cell phone. If we had a complaint, it's that the phone tended to pick up a bit of background noise on both ends. It wasn't enough to be distracting--we could use it in a busy place without any problems--but it was there. Speakerphone calls were satisfying, with quite loud volume and clear audio.
The Qualcomm 1GHz Snapdragon processor keeps things moving along relatively swiftly. We didn't notice a lag when opening features and we could switch back and forth between apps smoothly. On the data side, AT&T's ballyhooed HSPA+ network wasn't amazingly impressive. It fared just about the same as Verizon's 3G EV-DO Rev. A network and in some cases it even took longer. For example, the AT&T phone took 10 seconds to open the mobile CNET page and 32 seconds to open the full site. The Verizon phone, in comparison, opened the same pages in 6 seconds and 24 seconds respectively.
The Sony Ericsson Xperia Play has a rated battery life of 6 hours 25 minutes and a standby time of 17.7 days. That's a bit more standby time than the Verizon phone, but not as much talk time. According to the FCC, the Sony Ericsson Xperia Play has a digital SAR of 0.6 watt per kilogram.