Smartphones, Wi-Fi and GPS have made travelling easier, but a physical travel guide is always a smart investment when trotting the globe. Both Lonely Planet and Fodor's have been around for decades, but it's time to decide which guidebook deserves that coveted space in your travel bag.

Android/iOS: Lonely Planet is well known for their city guides, designed to help travellers around the globe make the most of their trips, and their new mobile app, Guides, brings all of that great information to your smartphone.

Lonely Planet has up to 50 per cent off all print and digital titles right now. Postage is free if you spend more than $50. Is this connected to Lonely Planet losing 50 million pounds in value since the BBC acquired it in 2007? Your call.

Lonely Planet has announced a series of new country guide iOS app. Starting with Italy, Ireland, France, Spain, Australia and Costa Rica, Lonely Planet says that they are the first of their kind from an expert travel guide publisher.

Continuing its long-standing practice, Lonely Planet is offering up its Austin, Texas iPhone guide for free, coinciding with SXSW. Another one to add to your collection if you don't happen to be in Texas for the festival (no, me neither).

Need a few key phrases in a European language for a forthcoming trip? Lonely Planet is offering free downloads of its QuickChat guides as PDFs this week, covering French, Italian, Polish, Portuguese, Spanish, Turkish and Filipino (which OK, isn't European). Handy.

The latest in Lonely Planet's free iPhone travel guide offers is for its Barcelona app, a deal which I strongly suspect is tied in to the Mobile World Congress happening this week in that fine city. As such, it's likely to run out at the end of the week, so grab it while you can.

We know Lonely Planet has a policy of making its iOS travel guides free in cities where travellers get stranded, and that it did so for snowed-in European locations over Christmas. Now it has a similar deal in place for North American cities suffering freak snowstorms, with 14 free guides on offer until Friday.

True to its philosophy of offering free guides during emergencies, Lonely Planet is offering iPhone city guides for 13 European locations for free to help out travellers stranded by snowstorms and bad weather.

Lonely Planet is offering its 25 Android Compass travel apps for 99 cents each between now and December 25. We liked them at full price ($4.99), so the 99 cent deal is definitely a good chance to grab a guide for any city you're thinking of visiting. The apps are available through the Android market.