I'd argue that adding "app" to your domain name *strengthens* your brand by making it more transparent and honest. It's accepted practice; see, for example, bufferapp.com and umergencyapp.com.

"Try__.com," on the other hand, is less advisable: it sounds tentative and uncertain.

For other URL options--slogans, extensions, puns--see my blog post: http://nancyfriedman.typepad.com/away_with_words/2014/02/a-pure-dot-com-domain-you-dont-need-it.html