Bought a printer, can't figure out how printing is supposed to work. HP M201dw is wireless and supports Wireless Direct, HP ePrint, mopia, Apple AirPrint, and maybe something else. Installed HP ePrint app on my Galaxy Tab S2 and my Galaxy S6 (and my iPad 4). Also installed mopia, cuz while the HP ePrint app will let me pick a file and print it, the mopia print service (I think) should let any app that has a Print button to print on my M201dw -- in other words, a service interface. ePrint, as an app, works, but printing from an app (like Chrome) doesn't. In Settings > Other Connections > Printing, I see print services by Samsung, HP, and mopia. But I'm confused. How is this stuff even SUPPOSED to work? If I turn on these print services, will they conflict? Will any of them allow me to print from an app (like Excel or Chrome) instead of only from a canned app like ePrint? I can't find mopia in any Android forum (Android Forums, Android Central, ...), so I guess no one is using it? Is everyone just picking files from ePrint and printing them? No one printing Web pages, for instance, or individual sheets from an Excel workbook? Thanks in advance.