Smartphones, being a fairly new sector in tech and still evolving on, one could say, a monthly basis, can sure become obsolete fast. A device that was top-notch last year is "adequate" this year, "usable" a year after, and "long due for upgrade" on the next. That's just how the cookie crumbles when it comes to new tech, we guess, as the same was true for PCs back in the '90s, when they were slowly becoming the mass-produced consumer item that they are now.
Useful things to do with an old smartphone
1. Fitness tracker
If you have an old iPhone 4s , you can update it to iOS 8, or if it's an Android handset that runs on Android 4.0+, you can download Google Fit – in both cases, you end up with a device that will run each platform's official fitness tracking app. This is a good idea, because a small iPhone or an old, beat-up Android phone are surely the better choice to have on you when you are engaging in a physical activity instead of risking, or just dirtying up, your shiny new handset. As a bonus, you can still use them to listen to music, or even stick your SIM card in when going for a workout, making sure that anyone who wants to get in touch will still be able to.
2. E-reader
Granted, older phones, with their smaller screens and inferior resolution are not the best choice for book-reading – you may still want to consider the option when going on a trip that will have you spending a long time between power outlets. Doing the reading on a phone that you otherwise wouldn't use, while keeping the battery of your main communications device undrained is probably a good idea.
3. Internet Radio
Plug it in a loudspeaker and run Spotify on it – instant makeshift radio! As a bonus, if you have an iPhone 4s or an Android 4.3+ device, you can couple it with your Apple Watch / Android Wear watch and remote-control the song playback as you walk around, doing your business. Pretty comfy.
4. IP Camera
A couple of weeks ago, we suggested a great app to turn your old smartphone or tablet into a home surveillance device, which you can monitor remotely. Pretty cool use, though, we'd recommend you make sure your “camera” doesn't overheat, as some of the old smartphones weren't made with constant video recording in mind.
5. Portable drive / SD card reader
It goes without saying that an old Android phone sure makes for an easy flash drive substitute or even SD card reader. Sure, the aforementioned devices aren't so expensive, or so rare that you'd have to come up with such makeshift methods, but for situations when you just don't have access to such gadgets – open that drawer and reach for the good ol' smartphone.
6. GPS tracker
How much this would be useful probably depends mostly on the old device's size. With all the “find my phone” functions and apps that have come out in recent years, you can easily use an old handset to track a specific item, person, or pet, while you are on a hike, for example. Strap that doggy backpack on Fido and let him carry his own water on one side, and his personal GPS tracker on the other – you know, for a peace of mind. This method will require a SIM card, though, so it's best to have an old prepaid one laying around, and be mindful of areas where there is low to no coverage. It's a makeshift tracker, after all.

more pix

Let me add

USE IT AS A SERVER!!

yes. You can use your Android phone as a full fledged Web server or Ftp server

http://lifehacker.com/5920173/use-your-android-phone-as-a-full-fledged-web-server

Let me add:
You can give it to a child as toy.

And what will my new phone be doing?

Use it as a Mobile Hotspot For playing Games that require Wifi like Modern Combat 5

It seems like a good smartphone should never really die then; it would always be useful.

Great! I already use my old iphone for extra storage

killzone:
Smartphones, being a fairly new sector in tech and still evolving on, one could say, a monthly basis, can sure become obsolete fast. A device that was top-notch last year is "adequate" this year, "usable" a year after, and "long due for upgrade" on the next. That's just how the cookie crumbles when it comes to new tech, we guess, as the same was true for PCs back in the '90s, when they were slowly becoming the mass-produced consumer item that they are now.
Useful things to do with an old smartphone
1. Fitness tracker
If you have an old iPhone 4s , you can update it to iOS 8, or if it's an Android handset that runs on Android 4.0+, you can download Google Fit – in both cases, you end up with a device that will run each platform's official fitness tracking app. This is a good idea, because a small iPhone or an old, beat-up Android phone are surely the better choice to have on you when you are engaging in a physical activity instead of risking, or just dirtying up, your shiny new handset. As a bonus, you can still use them to listen to music, or even stick your SIM card in when going for a workout, making sure that anyone who wants to get in touch will still be able to.
2. E-reader
Granted, older phones, with their smaller screens and inferior resolution are not the best choice for book-reading – you may still want to consider the option when going on a trip that will have you spending a long time between power outlets. Doing the reading on a phone that you otherwise wouldn't use, while keeping the battery of your main communications device undrained is probably a good idea.
3. Internet Radio
Plug it in a loudspeaker and run Spotify on it – instant makeshift radio! As a bonus, if you have an iPhone 4s or an Android 4.3+ device, you can couple it with your Apple Watch / Android Wear watch and remote-control the song playback as you walk around, doing your business. Pretty comfy.
4. IP Camera
A couple of weeks ago, we suggested a great app to turn your old smartphone or tablet into a home surveillance device, which you can monitor remotely. Pretty cool use, though, we'd recommend you make sure your “camera” doesn't overheat, as some of the old smartphones weren't made with constant video recording in mind.
5. Portable drive / SD card reader
It goes without saying that an old Android phone sure makes for an easy flash drive substitute or even SD card reader. Sure, the aforementioned devices aren't so expensive, or so rare that you'd have to come up with such makeshift methods, but for situations when you just don't have access to such gadgets – open that drawer and reach for the good ol' smartphone.
6. GPS tracker
How much this would be useful probably depends mostly on the old device's size. With all the “find my phone” functions and apps that have come out in recent years, you can easily use an old handset to track a specific item, person, or pet, while you are on a hike, for example. Strap that doggy backpack on Fido and let him carry his own water on one side, and his personal GPS tracker on the other – you know, for a peace of mind. This method will require a SIM card, though, so it's best to have an old prepaid one laying around, and be mindful of areas where there is low to no coverage. It's a makeshift tracker, after all.

[size=38pt]so you throw way your old smart phone? you can lie o [/size]

Abbey2sam:


[size=38pt]so you throw way your old smart phone? you can lie o [/size]

guy its just a post ni

You can conveniently use it as a Wifi Hotspot to connect all other device in your home.

Why not simply take it to Slot and exchange it for a new one?