No problem.
The printer problem for mobile devices is a huge cluster, and it's mostly because printing for computers has never been standardized. Instead of getting together and working out something nice and simply, every manufacturer has chosen to pursue their own standard, and build their own printer drivers for each major OS. Printing only looks easy on computers because they come with a huge number of printer drivers pre-installed, and software designed to go online and access an even larger database of priner drivers when that fails. It's a brute force method ill suited to the tighter resources of a mobile device. Especially when you consider that a computer only has to identify a few local printers. For a mobile device to have truly mobile printing it would need access to almost any printer driver made.
Adding mobile OS's to this mix is just doubling tripling (iOS, Android, Windows) the number of printer drivers that manufacturers need to create and distribute. This way of doing things needs to stop.
Apple's answer was to create the AirPrint standard and convincing a lot of manufacturers to adopt it. It does not support older printers, but for the printers it does support it will find and print to them without any extra special software or apps. It's not perfect, but that's Apple's answer for now, a standard.
Of course Apple is not the only one trying to fix this problem. HP introduced e-print. Google has their own printing solution. Etc. None of them agree on what the standard should look like, and, of course, there's money involved so. . .
So, like all standards past, we, the consumer are stuck with a fragmented set of solutions until either someone wins, or sanity breaks out.
Anyway, sorry for breaking out in more rambling.
Besides the apps you mentioned here are your printing choices for the iPad, in case you were not aware of a few. The pasted post is a bit out of date, but still close enough for a starting point. I really should take the time to update it.
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Some printers are directly compatible with AirPrint on the iPad. If you want this feature, be absolutely certain the printer supports AirPrint before buying. Some printers may require a firmware update to work. These are usually available on the manufacturers site. If you get this kind of printer you can print directly from within apps that support the feature, which is many.
AirPrint Basics
Of course some of us already have printers and do not want to buy a new one. There are several ways to do this.
One is to use a printing app on the iPad.
Most (or all) printing apps can only print pictures and/or files that have been copied to that app via Open In or another method. Several printer manufacturers have their own apps for their printers. In general those apps will probably have the best results, quality wise.
Another method is to load a program on the computer that will emulate an AirPrint compatible printer. Your computer must be on and have the printer available to it. The cheapest (free) is Airprint Activator. More features can be had with FingerPrint (mac and windows) and Printopia (mac only).
Printopia - Ecamm Network
FingerPrint - Collobos Software
How to Install AirPrint Activator for Windows?
A few printers (mostly HP's again) can be set up with their own email address. PDF attachments can be sent via this address to be printed. The last review I saw (many months ago) said it could be quite slow (big files not recommended), and sometimes the emails got lost and never printed. The advantage was that you could literally send/print from anywhere you have an internet connection.
For small business owners and those with more than one printer who would like all their printers to work, but don't want to leave a computer on all the time. The
Lantronix XPrintServer is a small box that connects to your network and is supposed to detect and make all your wireless printers available to iOS as AirPrint printers. I haven't seen a full review on it yet, so do your research.
Some NetGear router models support NetGear Genie, which will add AirPrint support for printers on your network. If the printer is not wireless, it must be shared on the network, and the computer it is connected to must be on.