With so many customers using smartphones and tablets to access online content your font of choice needs to work on small screens.
Best font for small text on screen. Use a large font that was designed for on-screen usage. The most legible fonts were Arial Courier and Verdana. Serif or sans serif is irrelvant.
You can start in the range of 10 to 20 but this is quite dynamic since different fonts need different settings. It was built on a foundation of geometric shapes to give the impression of friendliness. Since this font is smaller than other fonts it is great for longer pieces where you want to present a lot of information in a professional manner.
This is a sans-serif font and it is very popular because of its increased readability and ease-of-use. For inspiration look at the free fonts listed at the Google Web Fonts directory especially Vollkorn or the Droid Serif font which was particularly developed with small font size in mind. It is one of the easiest fonts to read on screen.
Both Pluto Sans and Pluto have the same range of. So in summary for now. Except for Jeff I guess The TV experience.
Use a size a couple notches smaller such as 13px or 14px. If readability is what you want Tisa is extremely legible in many text sizes while creating a unique design display. Arial is good in putting much info into a small space.
Oliver Sans Font is one clean and cool small caps font that will work equally well whether you need bold striking headlines or readable micro text. Georgia is a very nice sleek font that comes off very professionally. Quicksand another sans-serif font from Google does well on mobile devices.