It would be fantastic to be able to see the METAR of an airport without having to open it in the airport information menu. Two very good examples of this feature can be found on SkyVector and ForeFlight. Additionally, SkyVector and ForeFlight have a specific overlay to toggle this feature on and off. This will fit perfectly with the newly-released Navigraph Charts update that allows users to display METAR symbology on the map.
SkyVector: Layers → Text Weather (METAR/TAF)
ForeFlight: See the last screenshot.
See the following screenshots for reference: