I'm always checking on the usual suspects such as Twitter and Facebook, but Instagram and Pinterest are definitely firm favourites. I cannot stay away from Pinterest at the moment, it's addictive! I also highly rate the Bloglovin' app for keeping up with my favourite blogs - I mainly read posts on the train to and from work and the style of the feed is just super helpful for when I'm whizzing through areas with low signal as I don't have to open up any new pages.
It's not quite perfect but another app I use a lot is the Blogger app, to jot down drafts for new posts, publish posts when I'm out and about (I don't trust the schedule option as it has always let me down so far!) and generally just use for upkeep when I'm not near a computer. I feel it could be improved in terms of adding more editing functions as well as stats but it's perfect to tide you over until you next hit the laptop.
In order to feed my Instagram addiction I have a number of photography apps on my phone, the oldest of which is Hipstamatic - anyone remember that?? I prefer to take photos on the actual phone camera rather than through Instagram and then use a different app to edit where necessary. My latest fave is Afterlight - it has heaps of filters and you can layer them or adjust the image however you like. I'm going through a very bright, clear phase at the moment and Afterlight is perfect for achieving this (although I also enjoy the Instagram editing update!). A Beautiful Mess is another much-loved app for adding text or banners to images, it also has a few lovely filters and the option to purchase more if you like. Finally, my friends and I discovered a hilarious app named Pudding Cam (quite some time ago now!) which among others also has the option for a mock-fisheye lens - this makes for quite ridiculous results, especially on girlie nights!
As well as providing funny photo opportunities and keeping up with social media, I also use my phone as an encyclopedia of knowledge when out and about (as I'm sure most people do!). One of my recent discoveries which I adore is Zomato, it's essentially a social network for foodies and lists all the restaurants and bars in your area, as well as reviews and comments from other users. You also have the option to add a restaurant to your wishlist, or mark them as visited, or rate them out of 10... it's amazing and I adore it! The only thing I would say is it seems limited to major cities only (in the UK it serves London, Birmingham, Edinburgh, Glasgow and Manchester) but it also lists eateries across the globe and I can only imagine it will grow with time. It's free too!
Finally, the app I use the most is probably Whatsapp. My family live abroad and I do struggle with homesickness and loneliness on occasion, which is par for the course when you grow up in a house of six! However Whatsapp has proven to be a lifesaver as I can constantly text my family without the irritation of overseas charges; we share images, soundbites and pretty much anything you can think of, so it's the next best thing to actually being with them! I used to use Viber but now primarily just use that to make phonecalls when I'm abroad as the texting system wasn't great - it's excellent for staying in touch though as the calls take place over wifi (make sure you've got a good connection though!) and I just prefer it to Skype.
Obviously I also text, make phonecalls and check emails but that's not nearly as fun as messing around with apps now is it? The ones I have listed are all pretty popular so if you have any fun recommendations, obscure apps or handy tips please get in touch!