So you got that fancy new mobile device? What to do next? Back it up! That's what!
I update with new tips and apps in this section. I am an Android fan, so the iOS section is going to be sparse, to nonexistent for now, other than BACK IT UP! Especially before updating to a new version of iOS, and also before getting a new device. I follow All About Android on the TWiT.tv online network, and if you're really interested in Android, their Google+ community is a great one. I will often suggest an app that is not free because I don't mind supporting a developer, and it often gains me some great feature, like removing the ads. Most apps that are paid for, don't cost much, if they do, they probably are part of a service online as well.
After you've set up your backups(DO IT!), you probably will explore all sorts of features and tools built into your phone. You don't have to settle for whatever bloatware comes with it for doing things like listening to your favorite music, messaging such as text or email, and one of my most used features, the camera.
I'm a "Google fanboy" admittedly, but the reason is simple. They offer great services and tools. Start with Google's tools and apps for the things you want to do and you'll have a better, and easier, time of it. Link to Google's apps.
Photos and Video
For photos, start with Google Photos and Snapseed.
Google Photos is a new photo gallery from Google, made for the way you take photos today. Your photos and videos will be automatically backed up and organized, so you can find and share them faster - and never run out of space on your phone.
Snapseed is a complete and professional photo editor developed by Google.
Messaging. Oh wow is this one loaded! Most of us will be stuck with a bunch of apps because so many people use different platforms, email, SMS and MMS, video, and social media. There are also a lot of things to consider, like security and privacy, and they may extend far from your device.
Email - Seriously? Get Gmail, ditch the others. I'm not kidding, I have a whole section about how bad Yahoo email is. For almost all Android devices, Gmail is built in. I generally like to have a regular Gmail account, and have it be the place all your other email comes into, like your work, or other accounts. For an Android device, Gmail will let you do that on the device, and manage it all from one app. Many manufacturers put their own email clients on, but I have yet to see one that is as easy or smooth as the Gmail app. There are some other pretty good apps out there for email, but since I already have all my other accounts go to Gmail, I have a much easier time of it.
SMS and MMS - Lots to choose from here. I use the Android Messages app, from Google.