Disposing of waste regularly prevents your house from being junkyard and help to keep your house neat and clean. By disposing the old stuff, which are no longer in use, we will release an unwanted pressure of maintaining it which, in turn, saves our lot of valuable time.
The stuff which is not in use, is a waste for yourself irrespective of its cost. The value of stuff can be only realized by its use. If you are not using them, it will not provide any value to you, and it will also put an extra pressure on you for maintenance.
Hence, you can only derive a value from the old stuff be selling it or donating it to less privileged people. Always make a conscious effort to get rid of old stuff so that it can create a value by empty the place for new stuff.
In short, if you want to buy a new handset with more features make sure to dispose old one either by selling it or donating it first. Further, in the presence of a new handset, you are not going to use old one. Accumulation of any unused stuff will increase tension on account of the security and maintenance.