Do you buy new Phone or change Battery?

If the phone's still my daily carrier and is doing its job fairly all right, then no need to change it. Get an after market battery from AliExpress or something, swap the old one out and use for as long as it lasts. Pay attention to any kind of swelling or excessive heat though. Try to look into the kind of battery you're getting in the first place.

I go to the local repair shop and get a new battery, it always works out to be cheaper

My phones lasts for about 8 years. No way I can find a new battery for it to change.

Honestly. I have Samsung j6 and i have it for like 4-5 years. I planned to buy a new from Wish or overall from the China as my dad did. Very cheap I have to say. But I wouldnt mind to buy new battery for my current mobile as I like it and Iam very used to it after the years of repairing it and forever reinstalling Custom OS XD.

If you are working or have plenty of money, and youused your phonefor atleast 3 years. Than it is not an issue to upgrade the full phone. But the longer you hold up from buying a phone the more satisfied you will be when you get that new phone. So it is better ti be happy with what you have IF IT IS STILL WORKING.

buy a new phone cuz the phones are getting more advanced