I did find that manually added printers didn't always remain visible on the network. When using a D-Link DIR-655 router, I often had to go to the xPrintServer's console page and refresh the printer to make it visible again. On a Netgear WNDR4500 router, the manually added printers occasionally disappeared but came back after a few attempts to select a printer from the iOS device; I did not have to go to the xPrintServer to reactivate them as I did with the older DIR-655.
Choosing between the Network and Home editions. There are two versions of the xPrintServer: the $150 Network Edition, which supports an unlimited number of network-connected printers, though the company says performance degrades after about a dozen, and the $100 Home Edition, which supports just two network printers but as many as eight USB printers connected directly to the xPrintServer's USB port. (You'll need a USB hub to connect more than one printer to it.)
The value of that USB connection depends on whether you use USB printers and, if so, whether you also have a router that supports such printers, as most consumer-grade ones do today. If you have your printers connected to a router's USB port, that in effect makes them network printers visible to xPrintServer as a network printer -- you don't need to use the Home Edition's USB port.
Choosing between the Network Edition and the Home Edition comes down to the number of printers you have and whether you need a USB port to attach a printer to the network. The $50 price difference is only a small factor.
If you choose the Home Edition, note that Lantronix is serious about its two-network-printers limit. On your iOS device, you'll see all compatible network printers, listed in alphabetical order. But only the first two display as active, and this can be used for printing. If the two network printers you want to use with the Home Edition are not first on the list, access the Web console to hide the printers you don't want to appear. The pair you want will then be made active.
Working with USB printers. Both the Network Edition and Home Edition support USB printers, but in different ways. Unlike the Network Edition, the Home Edition lets you connect a USB printer directly to the xPrintServer or through a USB hub attached to it, which lets the xPrintServer autodetect and set up the printer for you. Both xPrintServer models support USB printers attached to routers on the network (that is, routers that have a USB port and built-in print servers, as many do today). However, you must go to the xPrintServer's Web console and manually add them in its administration pane. You need to know the printer name and model and its IP address for xPrintServer to AirPrint-enable them.
A side benefit of attaching a USB printer directly to the xPrintServer Home Edition: It makes that printer available not just to your iOS devices but also to your Macs and Windows PCs. OS X Lion and OS X Mountain Lion support AirPrint natively, so they'll see any USB printers attached to your xPrintServer in the Print & Scan system preference when you click the + icon button to add printers. On Windows, it's not so easy; Windows XP through 8 do not support AirPrint or its underlying Bonjour networking protocol, so Windows' native network printer detection will not see AirPrint printers. But Apple has a free utility  that solves this problem, detecting and installing AirPrint printers in Windows.
Limitations in the xPrintServer line. The one significant limitation to xPrintServer is its scale. It's really designed for small office and departmental networks, with one device plugged into each LAN segment. Each xPrintServer is individually managed, so an IT organization encompassing multiple LAN segments and locations that wants to centrally manage them needs to look at an enterprise-oriented server instead -- meaning EFI's PrintMe Mobile software for Windows.
My one wishlist for the xPrintServer is that it would work over Wi-Fi relay. It now requires an open Ethernet jack on your network where it can be plugged in. That's usually no big deal in a medium-size or larger company's office setting, but it can be problematic in a small office relying on consumer-grade routers that almost always come with just four (or fewer) wired Ethernet ports. They can fill up fast, leading to awkward daisy-chaining of slave routers.
Still, the xPrintServer is by far the easiest way to AirPrint-enable your printers. Unlike the applications that convert your Mac or PC into an AirPrint server, the xPrintServer works whether or not your computers are on. That way, you can print that boarding pass at 4 a.m. from your iPhone at home, without first starting up your computer.
AirPrint app clients on your computer: Cheaper but less flexible
Soon after Apple released iOS 4.2 and its AirPrint zero-configuration printing protocol in fall 2010, small-time developers figured out how to add the protocol to Macs and PCs, so they could act as waystations between iOS devices and printers connected to your computer. Finally, people could use existing printers rather than buy one of the still-limited number of AirPrint-enabled models.
Today, what had started as hacks shared by individual developers have evolved into several commercial products that add the AirPrint protocol to your computer. This approach means no need to get hardware and find a location to plug it into a power sources and to your network. But you also can't print from an iOS device unless the computer is on and the AirPrint service is running. That's fine much of the time, but can be inconvenient in a home office setting where you may be using your iPad, iPod Touch, or iPhone long after you've turned off your computer.
The three apps I tested were Collobos's $20 FingerPrint for Macs and Windows PCs, Ecamm Networks' $20 Printopia for Macs only, and Netgear's Genie app, which comes with its nicely designed WNDR and R series of consumer-grade routers ($125 to $200) in Windows and Mac versions. In all three cases, they work with printers directly connected to your computer via a cable or indirectly through the network; if the computer sees them, so do these apps. Although they do the same thing, they work a bit differently from one another.
Collobos's FingerPrint installs as a service you can manage through its background application, which you can access from the OS X menu bar or from the Windows task bar. You can get a version for OS X 10.6 Snow Leopard or later, or for Windows XP Service Pack 3 or later. The company also offers a time-limited, reduced-functionality trial version, so you can see if it works in your environment before paying for it.
When your computer starts up, so does the FingerPrint AirPrint service. In the background application, a list of printers attached to the current computer displays, and you select those you want to be visible to iOS devices. Click on a printer to see any configurable options for it, such as supported paper sizes, in the General pane. In FingerPrint, use the Security pane to set up user access restrictions for printers by associating any access control lists set up in your OS to them.
Once the FingerPrint service is running, iOS devices on the same network see the printers attached to your computer and can print to them through your computer, using its printer drivers. iOS's AirPrint service supports just basic printing options, such as number of copies and duplex printing, but FingerPrint supports even fewer. The duplex option, for example, doesn't appear, as it did for Printopia, Genie, the Lantronix xPrintServer appliances, and EFI's PrintMe Mobile.
FingerPrint also can "print" to JPEG or PDF files sent to your Mac or apps such as iPhoto, Dropbox, and Evernote.
Ecamm's OS X-only Printopia also installs as a service on Mac OX 10.5.8 Leopard or later, but you manage it through a system preference on the Mac. The company offers a time-limited trial version, so you can test it in your environment before buying.
Configuration options include paper size, color settings, toner efficiency, password protection for printers, the network port, and the printer icons in iOS's printer list to distinguish Printopia-enabled printers from other AirPrint printers). Like FingerPrint, it can "print" to JPEG or PDF files sent to your Mac or apps such as iPhoto and Evernote. Plus, you get the ability to select duplex printing for printers that offer that capability.
The simplest of the three application-based AirPrint options is the nicely designed Genie router-management app that comes with Netgear's WNDR and R series of wireless routers, as well as with its wireless repeaters. (I tested it with the WNDR3800, WNDR4500, and R6300 routers, all of which I really liked as routers.) You can download Genie from Netgear's website to as many Macs and Windows PCs as you have on your network -- there's no per-client price as with FingerPrint and Printopia.
There's a version for OS X 10.6 Snow Leopard or later, as well as for Windows XP Service Pack 3 or later. Note that the Genie iOS and Android clients let you manage your Netgear router but not AirPrint; you do that from the computer whose printers you are AirPrint-enabling. (It works only with selected -- meaning recent-model -- Netgear routers.)
On your computer, go to Genie's AirPrint pane and enable the printers you want to make AirPrint-compatible. That's it! As long as the computer and Genie app are running, its printers are available to iOS devices.
You don't get any of the printer configuration capabilities of FingerPrint or Printopia, nor their print-to-file capabilities. AirPrint support in Genie is simply one of several router management capabilities that Netgear offers -- a bonus of a sort. For most home and small-office environments, that's all you need. However, Genie's existence makes me wonder why Apple's own AirPort routers don't automatically AirPrint-enable network printers. Maybe Apple should license the technology from Netgear or Lantronix!
Keep in mind that although Genie comes with Netgear routers, the AirPrint service is not a network service like the Lantronix xPrintServer appliances and EFI's PrintMe Mobile server software  -- it is not running on the network but on your computers. At least one computer must be on running the Genie app for iOS devices to see its attached printers.
Making the right mobile printing choice
The decision as to what AirPrint option is best for your organization depends largely on the scale of your printing needs. EFI's PrintMe Mobile server software will typically be installed on a Windows Server, so organizations may need IT or network admin support to use it. It's also the most scalable of the AirPrint options, able to work across multiple network segments with central management. Plus, it's the only option to support Android-based printing, but it's the costliest and most complex mobile printing offering.
The xPrintServer Network Edition appliance is the simplest option for most work environments, as it can simply be plugged into an available network jack. If you need to do basic security and management, its Web-based console does the trick with little fuss -- though this management does not scale well across multiple network segments or allow central management of multiple xPrintServers. The Home Edition is a sensible option in a small-office or home setting where you have just a few printers, especially if USB models mainly comprise the mix.
The three software-based AirPrint options are the least desirable because they require leaving your computer on for iOS devices to be able to print through it. Of the three, I prefer Collobos's FingerPrint due to its OS X and Windows support. But I like Netgear's Genie application for environments that don't need configuration or print-to-file capabilities, as it's the least expensive option if you're also in the market for a high-speed wireless router or repeater.
This story, "6 AirPrint solutions for iPhones and iPads" was originally published by InfoWorld.