What actually makes a good reader gift for your dad?
Prioritize reading comfort, beautiful editions, useful accessories and book-adjacent objects that support the habit. For this relationship, it is also worth checking the activities he chooses when nobody is assigning him a task. Avoid choosing a random bestseller without knowing whether it matches their taste; also skip dad-joke merchandise unless that is genuinely his sense of humor. If you are unsure between two options, the less flashy product that fits an existing habit is usually the stronger choice.
The strongest gift ideas usually come from the person’s real habits: what they already use, what they talk about and what would make an existing interest better.
