the real value of something can only be judged when it's put to use
本当の価値は使ってみて初めてわかる (honto no kachi wa tsukatte mite hajimete wakaru)
"He claims the app is great, but the proof is in the pudding."
"彼はそのアプリが素晴らしいと言うが、証拠は使ってみてわかる。" (kare wa sono apuri ga subarashii to iu ga shoko wa tsukatte mite wakaru)
a person who is dangerously or foolishly creative or obsesse...
extremely pleased or happy
to plan your own path or future independently
to increase pressure or intensity
to spend money carelessly or extravagantly
not guilty or free from suspicion