The word perambulator 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: 23
Highest Scoring Words With Friends™ Plays In The Letters
Seven Letter Word Alert: (53 words)
ablator, aborter, aerator, amateur, ampoule, aptamer, areolar, aureola, aurorae, auroral, barmpot, bloater, blurter, bromate, brumate, erratum, laborer, marbler, maturer, mutable, oatmeal, outleap, palmate, parable, parlour, perturb, plateau, plouter, plumber, potable, poulter, praetor, probate, problem, prorate, protura, rambler, rampart, rapture, realtor, replumb, rubeola, rumbler, tableau, taboule, tabular, tamable, tempura, tramper, trample, trouble, trouper, tumbler