News that Google has purchased Sparrow for a reported $25 million have led many to wonder what’s to become of one of the most popular mail clients currently available for Mac and iOS. Many of our readers have asked what Sparrow alternatives are available in case Google shuts the service down for good. Unfortunately, the answer to that question is not too many, especially for iOS. Still, we did find a few.

Mac

Apple Mail

Many of the advantages that made Sparrow better than Apple’s own Mail client went away in 2011 with the arrival of OS X Lion, including Mail’s three-pane layout and unified inbox. Plus, Mail is fully intertwined with Apple’s iCloud ecosystem, which is also important for Mac users especially as OS X Mountain Lion is set to debut. Because of this, customers might wish to give Apple Mail another chance.

Cost: Free (with OS X)

Microsoft Office Outlook

Outlook for Mac

Outlook for Mac

Those who are seeking an all-inclusive mail solution should look no further than Microsoft’s Outlook application for Mac. Originally called Entourage, the application lets you unify your work and home messages, contacts, and calendars.  Unfortunately, the only way to get Outlook for your Mac is to purchase the entire Microsoft Office for Mac suite.

Cost: $199 (with suite)

Mozilla Thunderbird

Initially released in 2003, Mozilla Thunderbird is currently in its fourteenth release. The free application includes personalized email addresses, tabbed email, and the ability to customize your email experience through the use of Personas.

If you enjoy Mozilla Firefox, you will most likely feel comfortable using Mozilla Thunderbird. Other users may find the application dated.

Cost: Free

Postbox

Postbox Version 3

Postbox Version 3

If you really want to ditch Sparrow and have never liked Apple’s own Mail client, Postbox may be for you. The application offers conversations that are layered just like iOS and also supports a double-row vertical thread view. The latest 3.0 release includes native Gmail label support, “important” labels, and the ability to convert detected dates to Google Calendar events.

Additionally, profile photos from Facebook, LinkedIn, Twitter, Gravatar, and the Address Book are also available.

Other new features are listed here.

Cost: $9.95 (free for 30 days)

Our Pick: Postbox is a great Sparrow alternative, but we’d suggest those using OS X Lion look at Apple’s own Mail application again. You may be surprised just how much better the application has become.

iOS

Mail.app

One of the reasons you probably switched to Sparrow for iOS in the first place is you thought that Apple’s own native Mail app was lacking key features. However, with iOS 6, Mail gets better.

In addition to offering a more streamlined interface for easier reading and writing, Mail in the next version of iOS includes a VIP inbox and the ability to add photos and videos to email with just a few taps.

Cost: Free with iOS

eMailGanizer Pro

eMailGanizer Pro

eMailGanizer Pro

Available for $4.99, eMailGanizer includes a number of great features including the use of context folders. Unfortunately, it includes a nasty interface that looks like something circa the 1990s.

Cost: $4.99

Gmail

Most likely, the day will arrive when Google closes Sparrow for good. When they do, the company’s free Gmail app will likely be transformed to include many of Sparrow’s most popular features. Unfortunately, until Google does so, their current iOS app probably won’t satisfy current Sparrow customers.

Cost: Free

Our pick: We suggest keeping Sparrow for iOS and wait to see what Google does with it. While Sparrow in its current form could someday go away, we don’t know that with 100 percent certainty. With this in mind, keep enjoying Sparrow. Not sure what all the fuss is about? Check out our previous Sparrow for iOS review here.

If your email client for Mac or iOS isn’t listed here, please let us know.