- Phone, either mobile or desk.
- Computer, if you are not a very heavy user.
- Other devices:
- Camera, since picture quality is very high.
- Baby mobitor, if your operator/subscription allows it.
- Navigation/GPS device, thanks to Google Maps.
- Clock, alarm, watch and stop watch.
- Gaming device, portable console.
- Barcode scanner.
- Video:
- TV screen, second screen.
- Video player, DVD player.
- Remote control.
- Audio:
- Radio.
- CD player, MP3 player.
- Voice recorder.
- Other:
- Piano, if your musicality doesn't reach beyond fiddling with an on-screen keyboard.
- In time: wallet, keys, banking/credit card.
- If the technology is integrated into your Google Glasses, it obviously replaces your glasses as well.
- Once sensoring devices (movement, smell, air quality, etc.) will be integrated, the smartphone will also replace those kinds of hardware tools.
Not to mention access to all sorts of media and information services on paper and discs: dictionary, diary, newspaper, city map, cookbook, TV guide, photo album, CDs, DVDs, etc.
In short, the smartphone saves tons of resources and energy from the conversion of hardware, discs and paper into software and touch screens. And owning a personal device such as a very cool smartphone also reconsiles us with the fact of having a smaller screen and reduced audio quality, which in itself also saves us resources and energy.