This is a pretty forward question that requires a straightforward one piece with no possibilities answer.
I'm not a native English speaker or a dweller of an English speaking country, but I paid a hell lot of money to learn English from a native British nationalities in a fully certified learning centers that works in coordinate with the British embassy in my country.
I had to explain this intro because it has a lot to do with my question.
On surfing the internet and to be precise YouTube videos I found this.Just take a good look at the title of the video, Ok. I've encountered this a few times before in some other websites (like in comments, etc..) that I found people who write the indefinite article "a" instead of "an" in front of a noun that initiates with a letter vowel, but I really did not pay that much of an interest to what those people are writing as I assumed that they were not a native speaker nor live in country that speaks English.
Now that really pisses me off, like really. The boy in the video is supposed to be American (I guess to be fair, judging from the accent), and he is presumably the one who edited the title of the video, so why the hell is he making such a very big mistake making such an easy error and instead of writing the title like this : I Got an iPhone 7 Early he wrote it this "I Got a iPhone 7 Early". This is not what I paid my money for to learn English and my English native speaker teacher --regardless of his nationality which is British-- described that this is not legit to write such, this is not English. Americans might have some other different way from British but I'm sure they would agree on the part of the very pretty clear rule of definite and indefinite articles and that this is totally illegit to write such a thing.
However I'm seeing more and more people on the internet who also might be a native English speaker and commit such a very easy grammar mistake, Why ?
I guess the suggested answer does not resemble the example in my question (iphone). Have another opinion?, elaborate it in an answer.