#3 BlackBerry Playbook

The BlackBerry PlayBook was a tablet released in 2011, and sold in Canada and the United States. It was a first device to run BlackBerry Tablet OS, based on QNX Neutrino, and runs apps developed using Adobe AIR.

Early reviews were mixed saying that although the hardware was good, several features like lack of native email and calendaring programs, tethering requirement and others were missing. Shipments totaled approximately 500,000 units during the first quarter of sales and 200,000 in the following quarter.  Many of the 700,000 units shipped to retailers allegedly remained on the shelves for months, prompting BlackBerry to introduce dramatic price reductions, which only helped sales for shorter period.

#2 Cisco Cius

Cisco did bring out a tablet called “see-us.” You might not be familiar with the name since the device was dead before it could take its first breath. The Android-based tablet was announced by CEO John Chambers at CiscoLive 2010 and launched the following year.

The focus was on collaboration, video conferencing, office connectivity, and security -- attributes that Cisco thought would be big hits among its enterprise customers. The tablet seemed great, but price was steep at $750 and executives were already bringing iPads into the office with or without company’s approval. The CEO said, "Once you realize you're not going to reach the volumes you need, you should just stop."

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