Hey, there are many things that you can do with your smartphone and need not to spend money for such activites.... like there are many fitness apps - yoga apps, gymming apps, exercise apps etc that are free and can help you guide what type of exercises you can do by youself without going out for a gym!!
If you are having problem in your studies you can install various subject related applications in you phone that are free and helps you to learn your chapters. Best thing is that you don't have to pay any tusion fee and can learn anything anytime!!
There are many apps that let you send voice messages through web, so here you save your phone balance :)
You can pay your various bills directly through your phone, so your petrol bill is saved here :P .
If your phone camera is good then there is no need to buy a Dslr or Slr camera. You can shop via apps which provides many amazing offers and discounts..,, there are many more things through which you can save your money.
Hope I answered your question. :))
