DuBlast is an add-on for Blender which makes it easy to create and play animation playblasts, without having to change any render or output setting.
It adds an Animation Playblast entry in the View 3D > View menu.
It renders the animation with the current viewport settings, temporarily overriding the output settings. By default, it will render the animation with a resolution of 25% of the output dimensions, in the default temp folder for your system. It then automatically opens and plays the animation.
By default, the rendered animation is stored in an *MP4* file, with custom settings tweaked for better animation playback and seekability (it is easy to go frame by frame in these files).
You can adjust these and other settings for playblast creation in the Output Settings Tab of the Properties panel.