Wi-Fi support. In addition to 2.4GHz Wi-Fi networks, the iPad Mini (like the third- and fourth-generation iPads) supports 5GHz Wi-Fi networks, which usually provide faster connections and greater signal reach, letting you access the Internet in more places and faster. The Kindle Fire HD also supports both 2.4GHz and 5GHz Wi-Fi, though its Silk browser was still noticeably slower than the iPad Mini's and Nexus 7's. The old Nexus 7 supported only 2.4GHz networks, but the new Nexus 7 supports both 2.4GHz and 5GHz Wi-Fi.
The Web and Internet winner. The iPad Mini and the Nexus 7 outshine the Kindle Fire HD when it comes to their online capabilities, tying in this category as the best.
You don't get a media tablet to do work. But as more and more workers find themselves on perpetual call, your media tablet should provide at least first-level capabilities such as the ability to do work email and view documents in common formats. It's even better if you can use such devices to work on projects without having to find a computer somewhere.
An iPad Mini, because it's an iPad, has great support for Microsoft Exchange, in addition to IMAP and POP servers. If your company supports iPad access to corporate resources, your iPad Mini becomes just another iPad for both your company and you, giving you the most security of any mobile OS outside of the BlackBerry, as well as the greatest selection of effective mobile productivity apps. If you hadn't installed those apps on your iPad Mini, you can download them from the App Store at no charge if previously purchased for a work iPad. The only real difficulty you might face is dealing with the smaller screen and smaller keyboard for text-intensive work.
The Nexus 7 is your second-best bet for doing work from a media tablet. Its Android 4.3 "Jelly Bean" OS has solid security capabilities and Exchange support, its Email and Calendar apps are solid if unexceptional, and both Mobile Systems' OfficeSuite Pro and Google's Quickoffice HD Pro apps for Android are capable enough for most business work. Plus, as with the iPad Mini, you'll find apps for a wide variety of business needs, from Salesforce.com to SAP access. As with the iPad, any compatible apps you purchased for other Android tablets can be downloaded at no charge to your Nexus 7.
Of course, many enterprises refuse to support Android devices due to concerns over its malware-infested Play Store and Google's history of inattention to security. Even if your Nexus 7 or other Android tablet can help you out in an emergency, your company may or may not let you use it.
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