I had a bad first impresion with this phone. During the first 3 days of use the phone will crash every once in a while. And to get it back, you will need to remove the battery so that it resets. These crashes did not always occur in the same application. After the fourth day, things started to improve. Maybe due to a SIM update 9804 message, I received. This message apparently self installed something in the SIM card and this fixed the problems I was having. The SIM card contains T-Mobile network information.The next problem I had, occured after a week of use. The T-mobile network connection failed and I could not make calls from the phone. I had to call T-Mobile and they fix it within minutes. I had to turn the phone off (no reset) while they changed something in my account.The reason I am awarding 5 stars to this phone is that after that first bad impression, the phone has performed flawless for three weeks. Where the phone excels is in the exterior design (small and beautiful). The email performance is also excellent. The Internet is very useful for keeping track of your stock or reading news.If you have a rocky start with the phone, refer to [...] It is a very good source of information.