qksms

apse it from the list and display a new promo code at the bottom. The mobile app code was also very simple. First, check if the promo code is available (one API call); if so, enable premium and remove the code (another API call). The reason why it costed about $100 is because we had too many concurrent users: the Firebase free plan allows only 50 concurrent users, and at our peak we were seeing ~500. Since the promo was only for a day, we bought an expensive plan that got pro-rated for just that day. It was an extremely successful promotion. [3] The final result was very interactive. It was amazing to watch the codes disappear in real-time. It was like a game: you had to be fast to enter the code, because the codes were being used so quickly. All in all, I believe we made more money in people buying it anyways (despite the promotion) than it costed to serve it. And keep in mind we built the entire system in about 5 hours. And I'm not even a web developer. An actual web developer could have implemented this in an hour or two. For reference here is the entire JavaScript powering the promo code website: var all_codes = new Firebase("https://qksms-promo.firebaseio.com/public_codes"); all_codes.on('value', function(data){ $('#remaining').text(data.numChildren()); if (data.numChildren() === 0) { $('#status').text('No more codes!'); } }) all_codes.orderByValue().limitToFirst(12).on('child_added', function(data){ $('#status').remove(); var str = '<div class="code" id="'; str = str.concat(data.key()); str = str.concat('">'); str = str.concat(data.key()); str = str.concat('</div>'); $('#wrapper').append(str); $('#'.concat(data.key())).hide().fadeIn(300); }); all_codes.orderByValue().limitToFirst(12).on('child_removed', function(data){ $('#'.concat(data.key())).slideUp(300, function(){ $(this).remove(); }); }); [1] https://github.com/moezbhatti/qksms [2] http://qklabs.com/qksms-promo/ [3] https://www.reddit.com/r/Android/comments/36eix7/dev_a_year_...