The National Library of Medicine (NLM) Drug Information Portal is now available for mobile devices. http://druginfo.nlm.nih.gov/m.drugportal
This mobile optimized web site covers over 32,000 drugs and provides descriptions, drug names, pharmaceutical categories, and structural diagrams. Each record also features information links to 19 other resources including NLM PubMed, NLM LactMed, and Drugs@FDA.

Does this app also provide drug interactions? That is usually my biggest concern when I am sick and taking a bunch of things at once
Good Morning Carol,
Unfortunately, this app doesn’t provide that particular information. However, when looking up a prescription drug, you are given a list of information links that might provide you with that information. These additionals links are all sponsored by the National Library of Medicine.