The gift that doesn't wilt
Flowers last a week. This one keeps the photo of you two on the back of their phone, in soft paper-like color, every single day. Pick the photo together, or surprise them with one they forgot existed.
Anniversary
One year, five years, doesn't matter. Load the photo from where it all started.
Valentine's
Skip the queue at the flower shop. This one they'll still have in March.
Long distance
When you can't be there, your photo is. On the back of their phone, all day.