There is a vast difference between blocking and locking of a smart phone or mobile device and it’s important not to confuse the two.
A locked phone is when a phone will only function on a particular mobile network and is in effect locked to that network. This usually occurs when you take out a contract with a network provider on a brand-new phone so that they can subsidise the cost of the phone into your monthly payments and encourage you to stay with that network provider. It is however, possible to unlock a phone if you do want to change network providers and it isn’t illegal to do. You will often find unlocked phones available for purchase on second hand websites such as ebay or Gumtree.
A blocked phone, often referred to as blacklisted phone is an entirely different matter. This is when a phone has been compromised (stolen or lost) and has had a block put in place, usually by the rightful owners’ network operator. When a block is put in place, it is put on the phones IMEI (the number to individually identify each phone). This means that when someone inserts a SIM card in the phone and attempts to use it, the phone will not be able to join a network and therefore won’t work. It’s also useful to point out that countries such as the UK operate cross-network blocking which means a blocked / blacklisted phone will not operate on any network in that country!
To help avoid purchasing a blocked phone you can use CheckMEND to do a check on the device before you purchase it. All you need is the IMEI number of the device (which you can ask the seller for) and you can then get an instant check on the device which can inform any buying decisions www.checkmend.com