Interpolation is a very common mathematical operation which aviators use regularly to 'fill-in the gaps' when dealing with numeric data.
For example, most wind charts show the wind at specific locations (spot-wind charts). Thus, the estimation of the wind at specific locations might require interpolation, as illustrated here. Also, such charts are usually produced for specific levels (FL 050, FL100, FL180, etc.). So, the estimation of the wind at intermediate levels also requires the interpolation of wind vectors.
The interpolation of wind vectors is also very useful to determine the average wind along a given route profile; a key aspect in flight planning (see the Fuel planning page for more details).
The interpolation of wind vectors requires the calculation of the average wind intensity and of the mean direction.
The mobile application allows you to practice the interpolation of wind vectors. Have fun!