Why is the difference between American and British English important? 

Language has the basic task of transferring ideas between people. When one speaks, the one who is listening expects to receive recognizable 'codes' that translate into definite ideas. When we do not know the code, we will not understand the ideas. 

Now while British English and American English are very similar there are differences. I was speaking at an event in Washington DC, and I mentioned in British English that the "police put a torch in my face". After the event I was asked "If the police put a torch in your face why don't you have scars?" I was confused until someone pointed out that in American English a torch would be understood as distributing a flame. In American English, I should have used the (code) word 'flashlight". 

The American audience thought I was referring to an assault by a police officer with a flame, whereas I was referring to the fact he illuminated my face using a flashlight.

American English is spoken across the 50 states of America and in some smaller countries with strong American influence. Places like Puerto Rico, and the Philippines will be familiar with American English. However, the UK, Canada, Australia, New Zealand Ireland India and most Commonwealth countries will be familiar with British English.

That is why Blabla Live is a very useful and powerful app. Learners using Blabla Live can learn either British or American English or both. If you have a smartphone, you can learn to speak English with native speakers anywhere at any time. Blabla Live app helps you to learn to speak English under the direct guidance of both British and American native speakers. If you want to speak English with a genuine native English structure and accent, then learn to speak English using the Blabla Live app.