It definitely says 'to 8/11 23:59' in the event notice.
Have a countdown timer.
http://www.timeanddate.com/countdown/to?iso=20150811T235959&p0=248&msg=BGHS+2+Million+User+Giveaway+Entry+Deadline&font=slab
Or if you want to get it off Google Play for some reason.
We don't really cover TW because of the differences between the TW and JP versions.
/u/yellowike did a great job of describing the tasks to you, but in the future there's going to be a lot of moonspeak to try and decipher. Events, goals, girls' bust sizes, that sort of thing.
I highly recommend downloading the Google Translate app. You can take a screenshot, then load it up in that app and highlight the Japanese text to translate to English.
It's gonna be really broken, hard to understand. But you should be able to get the jist of it, so long as the app was able to correctly identify the characters. Just a small heads up, it'll try to translate names that are also words. For instance, Anko (the one with giant unruly twin tails AKA: The best) sometimes has her name translated to crab soup.