The word rangefinder is playable in Words With Friends™, no blanks required. Because it is longer than 7 letters, you would have to play off an existing word or do it in several moves.
Words With Friends™ Letter Score: 19
Highest Scoring Words With Friends™ Play In The Letters
Seven Letter Word Alert: (49 words)
adenine, angered, angrier, darning, definer, deraign, derange, dernier, drainer, earning, earring, engined, enraged, fearing, feeding, feigned, feigner, fending, ferried, freeing, fringed, fringer, gnarred, grained, grainer, grander, grenade, grinder, grinned, grinner, nearing, needing, nerdier, randier, rangier, readier, reading, rearing, reefing, refined, refiner, refired, refrain, refried, regrade, regrind, reigned, reigner, rending