11. Seismometer

Of course, Seismometer is a useless app for serious, um, seismographists – the iPhone isn't calibrated and so there's no scale shown on the display. But it's nevertheless quite fun seeing the iPhone's accelerometer record jolts to the iPhone on the table. It looks the part, too, with an actuator drawing a line on a continuously rolling sheet of graph paper.

12. Games console

There are now dozens of very high-quality games available for the iPhone and iPod touch platform. Super Monkey Ball, one of the first, is still one of the most polished, but with big releases such as SimCity, Brothers In Arms and Spore Origins, it looks like the big boys are here to stay. Jailbroken iPhones can run emulators, too.

13. Number pad

The keyboard on laptops is generally fine, but if you want to punch in loads of numbers, using the horizontal strip of numbers along the top of the keyboard it's a pain. But NumberKey connects to your Mac laptop over your WiFi network. Of course you don't get tactile feedback, but the audible click is good enough.

14. Language tutor

While none of the big names in language tuition has released full apps for the iPhone, we can only imagine it's impending. There are lots of dictionaries and phrasebooks with lastminute.com offering the best. Available in French, German, Greece, Italian, Portuguese and Spanish, they tote some handy phrases with good audio read-outs.

15. Ice-breaker

When the conversation lulls, pull out your iPhone. OldBooth is a brilliant app that lets you put the faces of your friends, colleagues and fellow party-goers onto the heads of classic American yearbook-style shots. The implementation is beautiful, and the results, especially if you follow the tips, are genuinely impressive.

16. Remote control

There are many ways to use your iPhone as a remote control that we can barely fit them in. Apple makes two apps. Remote controls your iTunes connection over your Wi-Fi network, and Keynote Remote lets you control presentations running in the version of Keynote that comes with iWork '09. But the developer community has produced some cracking little apps. Air Mouse is one of our favourites; it gives you a virtual keyboard and mouse on your iPhone that you can use to control your Mac – great if you use a Mac as a media server, for example – and you can control the cursor trackpad-style or by waving your iPhone around. LogMeIn Ignition (£17.99) lets you assume full control of Macs and PCs over the internet, and if you liked the sound of Keynote Remote but haven't upgraded to iWork '09, investigate StageHand.

17. External storage device

We still have a soft spot for the slick and well-engineered FileMagnet app, which lets you load docs onto your iPhone – and view many popular file types when you are on the go. But it does, annoyingly, mean you have to have a helper app installed on the computer you want to connect to. If you want to copy some photos, say, to your mum's Mac, it's hardly convenient to have to install the helper app first. Air Sharing gets round this by, effectively, turning your iPhone into a little NAS (Network-Attached Storage) device. Launch it, and it tells you what IP address your phone is on the network. You can then use the Connect to Server command in the Mac to mount it as a network drive. It works on Windows XP and Vista, and Linux too, so it should be possible to connect it to any computer you may come across. Performance is good, and while it struggled a little when asked to view complex documents on the iPhone, it is generally very robust.

18. Atomic clock

The CS2 Atomic Clock app syncs with Apple's European or US time servers to get the precise current time. Yes, it's pointless, but we think it's fun, and the display closely mimics that of the original CS2 atomic clock in Germany. There's a nighttime mode as well so when your baby wakes you up in the night you can be sure exactly how much sleep you're not getting.

19. Make VoIP calls

Guilty: the Truphone app is of less use for iPhone users who already have a phone in their device – though even they could benefit from the cheaper calls from this VoIP service – but for iPod touch users, this is a boon. Pair the second-generation iPod touch with a compatible headset, and it has suddenly become a phone. Some folks are reporting flakiness, however.

20. Settle arguments

If you find yourself without a coin to flip to decide whether you go and see Beverly Hills Chihuahua or Quantum of Solace, try a coin flipper for the iPhone such as iHandy Coin Flip. And the very beautiful physics of MotionX Dice – giving you up to six dice – will dazzle and distract you as you use them to pick from a richer set of options. Free counselling!

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First published in MacFormat, Issue 205

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