The reason I love Wordiest is that it reports how I did against 100 others, as well provides a continuous graph of this measure, keeping me coming back to try and improve. Also, their integration of Wiktionary ensures I'm constantly learning new words and getting reacquainted with ones that I'd forgotten. The only person I'm competing against is myself. Also, it works whether I'm online or offline - explaining it's longevity on my phone.
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