So, if you buy a SIM card from a network other than your Android device, you can not call or use their services. You must call your mobile operator to unlock the phone. The plan has completed or paid the entire contract amount. 1. Check if your Android phone with your SIM card is unlocked or not. The easiest and easiest way to check if your Android phone is unlocked or locked is to switch your phone SIM card to another SIM card, the device is locked. IMEI.info uses to provide free service to check the beginning and end of the contract so that you can understand whether it is locked or unlocked. For example, most American phones in Canada and vice versa because telecom companies use similar bands, or the phones are made to be compatible, all North American bands because that is where they are sold. Comes handy if you want to unlock your phone and spend it on a cheaper network or if you travel abroad and do not want roaming charges or if you want to sell the phone and only get more money for the phone. Another way to check if your phone is locked is to use a SIM card from someone other than your network operator from whom you purchased your phone. If you can successfully talk to another mobile service provider SIM card, the phone will unlock. But if you can not, phone carrier is locked and you need to talk to the carrier to unlock it. UnlockBase claims to offer the best price in the industry so if you find another service provider offering the same service, contact them for a lower price. Unlock Samsung Phone Forgot Pattern Cheap Unlock Codes For Iphone 4s. here. One of the benefits of using this method is that you can unlock your phone with the same service. IMEI.info gives you a free unlock service for your device when it is tied to a carrier. If they could reduce the price a bit, it would be good, but I think you pay the price for quick and accurate service (what was it that I needed).