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
It will not matter.
You have to look at the strategy of how you plan on acquiring users for the website.
For Example: If you are going to leverage Social Media your in-bound traffic is going to be coming in the way of clicking so your domain name makes no difference.
Another Example: Email Marketing, the user is clicking on a link of sorts so the domain is a non-issue.
If you have more questions shoot me a message.
As a professional in the domain industry, I'm expected to tell you that an "exact match" domain is indispensable for gaining traffic for the keyword or name you want to be found for ... and that adding an extra word to cut costs would hinder your SEO.
But I'm not going to say that. Choose your domain based on how PEOPLE are going to interact with it, and search engines be damned!
Once upon a time, if the words in the domain precisely corresponded to the words in a Google query, then that domain would receive an automatic boost to its rankings, whether the domain contained quality content or rubbish.
But Google algorithms have changed. My understanding is that the SEO advantage for an exact-match domain won't be seen unless the website has multiple reinforcing indicators of quality and trust. In other words, there's no shortcut; but there may be a long-term SEO benefit.
The more important questions you ought to be asking are:
(1) Will customers remember the domain with some extra word as well as they'd remember the simpler domain with just my brand name?
(2) Will I face extra confusion and competition in search results (leading to higher CPC advertising) if I allow someone else to own a domain matching mine but without the appendage word? Even if they're not competing for your customers, they'll be competing for that #1 spot.
(3) How will passers by view my brand differently if I add extra words, given that the best brands don't cut corners?
Remember, it's Amazon.com not TryAmazon.com. And it's Twitter.com not, say, TwitterApp.com. Even Facebook.com got rid of the "The" from TheFacebook.com. You have a gut reaction to these extra words. So do the people you want to win over. Put your best foot forward.
Sometimes adding an extra word is fine, or even better. And sometimes it's just a way to cut corners that can lead to trouble or extra cost in the future -- possibly in the form of high customer acquisition / retention costs, possibly due to an AdWords bidding war, and possibly due to a domain upgrade made more expensive by your own success.
I practice what I preach, by the way. Although I could save money by adding extra words to my brands, I generally choose to pay up in order to do things the ideal way.
For instance, I'll be launching my naming practice at some point at Overtone.com ... not at MeetOvertone.com. And when it comes time for me to launch a magazine at American.org, I will have a networking advantage with that domain as my calling card versus, say, ReadAmerican.org. Likewise, UKProperty.com means something different to people than UKPropertyFinder.com. At the moment I'm scraping together my pennies to buy a 5-figure domain for another project I'm working on too. None of this with venture capital or partners. All with my own hard-earned dough.
There's no right answer. But think it through seriously.
From a SEO perspective it wont hurt you, but try to stick to short domain names they are easier to remember. 5 letter word an even 7 are the best. There are many sites that have "downscaled" their domain name to get better brand recognition like Pandodaily.com into pando.com Angellist.com into Angel.co and many more. Might want to experiment with rare domain extensions such as .io, to get just your name brand without the "app" or "get" to keep it short.