For starters,I understand your situaion and how you feel about it, but let me tell you that you are the first boy i meet obviously who the priority is his studies. I'm so happy for you, many people think that they have to keep up with the latest trend and they do not care about money. Young people think that all it is about material things and leave out what really matter in their life as their studies.
Second, it is totally true that it's important to keeping up with trends, for example, tablets you can take it with you wherever you go and i you need send ormaybe search some information your tablet can be your hero so notonly technology it is important, fashion is important too, because you have to know what kind of clothe is being used, because you can not wear clothe like 80's
In the third place, there are ways to keep up with trends, for example television is a good way to watch news around the world, radio you can listen news too while you are going at work or your house. Young people tend to be aware of everything that happens through their smart phone but if you don't want spend a lot of time you can check your cell phone but not matter if you don't have a new cell phone all the cell phone has radio so you can check once or twice. To keep up with trends is not becesary spend too much money, there are newspapers to read when you back home or when you walk to school.
To conclude, i think that it is your life your friends don't have to decide for yourself. If you are happy with really basic things, it is ok, be proud of who you are and the things you have, things not last forever but your studies yes, so material things can't define how much you have or who are you , don't let society change your mine.
I hope i can help you