Table 1.

Social media characteristics.

Social media form		Information richness	Social presence	Social Support Scale 1-6
Blogger or WordPress editable pages or wikis such as
	Wikipedia	Essays and short reports via blogs	Blogs; narrative or storytelling	1-2
	Google Docs
Audio sharing through Clyp or SoundCloud		Music and voice	Collective experience and content community	4
Videos and collaborative spaces distributed through services
	Pinterest	Music, voice, video, collaboration, and reviews	Collective experience and content community	4
	YouTube
	Vimeo
	Viddy
Combined, multipurpose platforms that offer multiple media options
	Facebook	Essays, short reports, and links to articles	Social network; pictures; videos; messaging; leaders and followers	5
	Ning
	LinkedIn
	Skype
Short-form text messaging and photo sharing
	Twitter	Texting: music, movies, books, maps, voice, high quality photos, and videos	Social network; pictures; immediacy; reach; leaders and followers	5
	Instagram
	Snapchat
	Gtalk
Mobile health (mHealth) apps
	eHealth record	Practice of public health and medicine through mobile devices	Collective experience; content community; information; motivation; support; remote monitoring; diagnostics and decision support	6
	Social health
	Web-based health communities
	Fitness apps
	Personally controlled health management systems (PCHMS)
Gamification (serious health gaming)
	Multiuser Dungeons (MUD)	Virtual social worlds with identities and collaborative content; challenge; competition; avatars	Collective experience; content community; shared emotional states; social network; social influence	6
	Re-Mission2
	DietBet