Congrats for ordering the phone. Is this your first Windows Phone?
What erzhik (previous post) said is totally correct. You will get used to the size very quickly, and in no time will not see it that big any more.
As for apps, don't let others tell you what to install. Customize your Windows Phone experience to your own taste.
I got the Lumia 1520.3 myself last month and I'm very happy with it. It's the phone I've been waiting for during the past 7 years, as it's the first real phone I get since my Nokia N95
Technically it isn't my "first" Windows Phone. I ordered a HTC Surround 7 about 4-ish years ago, used it for about 9 seconds then gave it to my Mother because she needed a new phone.
I have wanted a "Lumia" (all versions, really) since around 2009, so having this as my main driver will be too exciting to gripe at.
And yeah the size took me by surprise when I used a test phone at my local Nokia retailer. But it wasn't nearly as bigger shock as when I unboxed my Samsung Galaxy S3 (BIG mistake!) after owning an iPhone 4. The jump won't be too bad....I don't think. But even with the Samsung I have difficulty using a smaller screen (iOS etc..), so this will probably make it harder.
I think the main apps like 6tag, 6snap, Twitter-clients and things that people can recommend, but so far I'm searching these forums looking for suggestions and developer-highlights.
I have no idea what model I've ordered. All I know it's an International one, 32GB w/ 4G LTE and Qi. Yellow <3 The colour I've wanted for a while.
Jumping from Android, my friend said to install the 8.1 DP as soon as I get the device so the "shock" won't be as bad. Can't say I use the Multi-tasking screen in Android all too often though. However, the "Notification Drawer" will be missed. I believe 8.1 restores/adds that?
Needless to say that I am excited. The thread about factory issues worries me a little, but I'm sure the "Good Units" outweigh the "Bad Units" by far. Most of the issues seemed to be nitpicking anyway, aside from screen issues.
I'm glad most people seem happy with this. I was holding off on a Lumia purchase as the screen size was less than my Samsung --- but before I bought the Samsung I wanted a 920 and was convinced out of it by an Android-loving salesclerk --- and then Nokia do this. INSTA-WANT!
Thanks everybody for your suggestions. I look forward to contributing more next week when it arrives. I might even take the day off Uni to play with it as it's the last week of classes. Heh!