[GUIDE] How to enable Adobe Flash support in Android 4.4 KitKat

With the launch of Android 4.1 Jelly Bean in June 2012, Adobe stopped developing Flash for mobile and the out-of-the-box support for the technology disappeared. The door for Flash remained opened until Android 4.3 Jelly Bean, though, as the AOSP Android browser shipping on every smartphone still supported Flash. While Google Chrome for Mobile did not support Flash, browsers like Dolphin and Puffin (among others) allows users to easily playback Flash content.

With Android 4.4 KitKat (and all future versions), Google will use Chrome as its default web browser, which means Android has absolutely no support for Adobe Flash. Sadly several website still heavily rely on Flash, and the lack of support will leave these pages with huge blank spots instead of a video or other Flash content. Luckily there is a work around to get Flash working on your Android 4.4 KitKat device.

The following method makes use of the Dolphin web browser and a hacked version of Adobe's Flash Player.  It also requires you to allow side-loading applications, so that you can actually install the hacked Flash player that makes it all possible.

The process has been successfully tested on a Google Nexus 5 and should also work on any other devices which have recently been updated to Android KitKat.

1. Download Dolphin Browser  from the Google Play Store
   [WARNING] You must download the Dolphin Jetpack in the Google Play as well. As far as I have noticed, Dolphin Jetpack better solves the compatibility with flash player, such as crash issue & freeze issue in full screen.
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2. Download Dolphin Jetpack from the Google Play Store.
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3. Download the hacked Flash Player for Android
   [WARNING] Make sure that you have uninstall the flash player installed in your device and then install the hacked one for compatibility reason.
   
   If your devices refused to install apk outside Google Play, you may set in your device (Settings > Securities > Unknown resources) to allow installation of apps from unknown sources.
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4. Make sure that the flash setting in Dolphin Browser (Click Menu > Settings > Web Content > Flash Player) is on.

Keep in mind that since this is not an official release, you are likely to face your share of issues. Additionally due to the lack of official support enabling Flash comes with enabling all the vulnerabilities of the technology.

source - XDA Developers