With the speedy advance of technology, most of the people that I know buy a new cellphone every 2-3 years and it's not too difficult to spend over $600 on each new phone. Here's one tip to stretch your "investment" a little farther.
One way to make you phone budget stretch a little farther is to replace the battery in your phone. This accomplishes 2 things:
I have had good luck finding replacement batteries on Amazon. Amazon has a large number of sellers and a very wide variety of batteries. Most importantly, there are a lot of reviews, so you can often tell if a particular seller/manufacturer/battery is reliable or not. If your phone features a removable battery, search for the model# of the battery or search for the model# of your phone. You may see extended/larger capacity batteries. Extended batteries are more expensive, physically larger, but can offer 2x - 3x the battery life of stock batteries.
While your phone is still relatively new, you may be able to buy spare batteries from your cellphone provider. I don't recommend this route because they tend to be overpriced and you won't have access to any reviews about the battery when you buy it from your cellphone provider.
Be sure to read reviews before you buy a spare battery online.
Most cellphone manufacturers have abandoned removable batteries, making it harder and more expensive to replace the battery. It is very likely that your non-removable battery can still be replaced, it will just take some extra effort and a few specialized tools to disassemble your phone to swap the battery. ifixit.com has stepped up and does battery replacement tutorials and sells spares batteries and toolkits to help you replace your own batteries. If you are not handy with tools, many independent cellphone stores and battery specialty stores now offer battery replacement services.
Whichever way you decide to change your battery, replacing the battery can be an economical way to get your cellphone to last longer.