DuckDuckGo as the default BlackBerry 10 browser search engine
I started using DuckDuckGo as my default search engine recently (See their about page if you haven't heard of it before) and wanted to use it on my phone too.
To my (pleasant) surprise, I found they had a dedicated page describing how to set the BB10 browser search engine in a step-by-step manner complete with screenshots! In the last line they also link to CrackBerry's article about sideloading APKs and provide a link to their APK for the app if you want an app.
Check it out! https://duck.co/help/mobile/blackberry