Ever since technology has been taking over the place of physical books and offering users the luxury of reading their favorite book on their tablets, a war has broken out among major brands to lure customers this way. Apple's iPad Mini, Amazon's Fire HD and Google's Nexus 7 have been some of the top contenders.

Here is a comparison based on their specifications:

The Nexus 7 has a 7-inch IPS LCD screen with 1,280 x 800 pixels resolution. It runs on Nvidia Tegra 3 processor and Android 4.1 Jelly Bean. It has 8/16GB onboard storage and 1GB of RAM. It has a 1.2 megapixel front-facing camera and features NFC and GPS. It has 10 hours of battery life. The 8GB sells for $199 and the 16GB sells for $249.

The new Kindle Fire HD 7-inch tablet comes in 16GB or 32GB. It runs on a custom Android operating system. It has a 1280 x 800 HD display with polarizing filter and anti-glare technology for rich color and deep contrast from any viewing angle. It features Dolby audio and dual-driver stereo speakers. Amazon says that its dual-band, dual-antenna Wi-Fi does 40 percent faster downloads and streaming compared to the iPad 3. It has a 1.2 Ghz dual-core processor with Imagination PowerVR 3D graphics core, with free unlimited cloud storage for Amazon content. It also has reduced screen glare. It costs $199 for the 16GB model.

The iPad Mini has a 7.9-inch IPS LCD screen and runs on Apple's new iOS 6 software. It is 23 percent thinner than the fourth-generation iPad, according to USA Today. It has a display screen resolution of 1,024 x 768 and has a 35 percent larger display area than the Google Nexus 7, and is 67 percent larger to surf the Web. It has a A5 dual-core chip, and a 5-megapixel iSight camera on the rear of the tablet which can shoot 1080p HD video, 4G LTE and Wi-Fi support, as well as the new Lightning connector available on the iPhone 5. It comes with a FaceTime HD camera and 10 hours of battery life. It has Wi-Fi that is twice as fast as previous generation iPads. It will sell for $329 for the 16GB model.