Rome2Rio is essentially a trip planner, which will tell you how to get from point A to point B, anywhere in the world. It searches planes, trains, buses, ferries, and driving options to give you the shortest trip, and the cheapest trip. There's also a web version here.
While apps like Yelp and UrbanSpoon can find highly-rated restaurants near you, this app lets you search by dish. If you've got a big craving for spaghetti bolognese, but have no idea where to find it, this app will let you know. It's based on user submissions, so you'll obviously get better results in big cities than random towns in the middle of nowhere.
You can translate words in Google, just by typing "what is dog in spanish" into the search bar. The mobile app is even better though, with 52 languages available offline. You can also use your camera to take photos of text that you need translated.
10. Here WeGo
Here WeGo is perfect when you're visiting a big city. It'll help you navigate your way around without getting lost, with options for walking, driving, train, bus, and bike. You can download certain maps to use offline.
Tell the app where you want to fly to, and you'll be given tips on the best time to buy for a cheap ticket. It'll also alert you to deals and what times of the year is best to fly for cheaper. You can book tickets straight from the app, though a few users have commented that you can often find cheaper flights on SkyScanner. Just use Hopper for the inside intel on when to book.
This is a great app if you're planning to stay in hostels. It'll give you a run-down of all the hostels in a certain city, listing their amenities and room types. The best part is the user reviews, so you can make sure you're not going to be staying in a bedbug's haven with dirty toilets.