Hostelworld

The official Hostelworld.com app for Android offers you the possibility of making reservations in hostels, hotels, and inns in more than 180 countries around the world.

To make a reservation, just search for the city where you want to spend a few days, then mark the dates you're going to be there and the number of people who are staying (for up to eight people).

One of the great advantages in Hostelworld is that you can find rooms with more than 65% discount in almost all cases. And they don't charge commission, either, so you can start saving money while you travel.

For each lodging you can reserve the type of room you want, but before choosing it you can see a list of prices per night, so you can make sure how much you'll pay before making a reservation. The app also shows the services provided by the hostel, and a list of reviews written by people who've stayed there.