Although MLA does not yet have a clear policy about how to cite apps, most examples follow basically the same pattern for citing any kind of computer software. If you have questions, check with your instructor. For example:
Castanza, George. Acceptable Bathroom Locater. Computer Software. Apple App Store.
Vers. 1.2. Fictional Publisher, 5 May 2010. Web. 6 June 2012.
Cite a blog as you would an entire Web site Give the author’s name; the title of the blog, italicized; the sponsor or publisher of the blog (use “N.p.” if there is none); and the date of most recent update. Then give the medium and your date of access:
Mayer, Caroline. The Checkout. Washington Post, 27 Apr. 2006. Web.
19 Jan. 2007.
If citing a single blog entry or comment, follow the above example and add the author and title of the entry or comment. If this information is unavailable, use the terms "weblog entry" or "weblog comment" instead:
Mayer, Caroline. “Some Surprising Findings about Identity Theft.” The Checkout.
Washington Post, 28 Feb. 2006. Web. 19 Jan. 2007.
Burdick, Dennis. Weblog comment. The Checkout. Washington Post, 28 Feb. 2006. Web. 19 Jan. 2007.
begin with the writer’s name and the subject line. Then write “Message to” followed by the name of the recipient. End with the date of the message and the medium (“E-mail”):
Lowe, Walter. “Review questions.” Message to the author. 15 Mar. 2007. E-mail.
Start with the author name, then the "title of the post" (if available). Facebook.com. Date of posting. Web. Date Accessed.
Smith, John. "Comment about Citing Facebook." Facebook.com. 5 May 2012. Web. 6 May 2012.
When possible, cite archived versions of postings so that it can be accessed by others. If this is not possible, keep a copy of the posting for your records. Begin with the author’s name, followed by the title or subject line, in quotation marks (use the label “Online posting” if the posting has no title); the title of the Web site on which the discussion list is found, italicized; the sponsor or publisher of the site (use “N.p.” if there is none); the date of publication; the medium; and your date of access:
Fainton, Peter. “Re: Backlash against New Labour.” Media Lens Message Board.
Media Lens, 7 May 2008. Web. 2 June 2008.
Begin the entry in the works cited list with the author’s real name followed by the Twitter handle in parentheses. If only the Twitter handle is known, just use that. For example:
Since Tweets don't have titles, provide the entire text of the tweet in quotation marks, without changing the capitalization. Conclude the entry with the date and time of the message and the medium of publication (Tweet).
Also, since the time & date stamp on Tweets varies according to time zone, you should just rely on the day/time they see without worrying about converting it to the day/time it was actually posted. These are intended to be approximations only. For example:
Smith, John (#JohnSmith). “How to Cite a Tweet.” 5 May 2012, 3:58 p.m. Tweet.
In the main text of the paper, a tweet is cited in its entirety:
“How to cite a tweet” (Smith).
Treat a wiki as you would a short work from a Web site. Because wikis are collectively edited and continually updated, do not include an author. Include the title of the entry; the name of the wiki, italicized; the sponsor or publisher of the wiki (use “N.p.” if there is none); the date of last update; the medium; and your date of access.
"Hip Hop Music." Wikipedia.. Wikipedia Foundation, 2 Mar. 2006. Web. 18 Mar. 2006.