Sindarin dictionary+Phrasebook for Android
It works pretty smoothly, but for a Sindarin translator this has several weaknesses. It doesn't list BDG words that come from MB ND and ÑG. It doesn't tell you which words are actually Noldorin in origin. It doesn't list irregular plurals or tenses. And, it doesn't tell you the Sundómar of verbs, or their classification (A-verb, TA-verb, I-verb). If you already have this information memorized, you could use this without much trouble, but most people don't have that strong a grasp on the language.
by B####:
Really accurate!