Hmm, free traffic is always harder - social interaction is key.
FREE TRAFFIC
I'd recommend Facebook and Pinterest. I forget the link but there was this study that showed that those two had the most chance of stuff going viral. Look at IFTTT (
http://ifttt.com) to help automate that stuff. Build virality into your app - ultimately that's what you're looking for. There's loads of stuff on making stuff viral, let me show you:
http://lmgtfy.com/?q=how+to+make+viral+apps.
PAID BOOST
What you
could do with your blogs is boost them in the SERPs with parasites or something. Cost you about $166, and that's to buy Scrapebox
http://www.scrapebox.com/bhw (BHW discount) and GSA Search Engine Ranker
http://search-engine-ranker.gsa-online.de/
A good guide is here:
http://www.blackhatworld.com/blackh...w-comp-keywords-google-page-1-30-45-days.html or here:
http://www.blackhatworld.com/blackh...9-parasites-pwn-leeching-authority-sites.html
Set up a blog or three, review maybe a hundred apps (just rewrite your reviews or whatever), then post them at a rate of a hundred a day. At twenty apps posted, use the ranking method in the link above. Rank your blogs for keywords - look for them using adwords and google keywords planner - get an account by showing them your blog (only one blog though).
Continue posting, rank and rank - until at least you have thousands of UVs a day altogether.
Post GLOWING recommendations of your mobile apps. BUT, to make sure that they are not all at the same time (and people are unsuspicious that the blogs are all by the same person), stagger them out over a couple days.
Say that the app is horrible (like 3/10) because of some ridiculously tiny reason - e.g. fantastic functionality blah blah blah, addictive, blah blah blah, don't like the colour. Make sure that you ridiculously overemphasize one point. Obviously only do this sort of thing on one blog. But the key is to switch it up. Clickbaity titles will make sure people read your posts!
(Sorry for the writing - my head's pretty discombobulated recently. Just word vomit, word vomit everywhere

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