On the face of it
Definition 1 of 1
Pro Tip 1/3Initial Impressions
Emphasizes that a conclusion is drawn from the first, superficial understanding of a situation. 
On the face of it, he seems friendly, but that may not be the full story.
Pro Tip 2/3Deceptive Appearances
Suggests that appearances might be misleading, and more information could alter our view. 
On the face of it, their marriage is happy, but only they know the truth.
Pro Tip 3/3Critical Thinking
Encourages not to accept things at surface value and to look beyond initial observations. 
The contract looks good on the face of it, but scrutinize the terms before signing.