My 3 Months Old and 17 Days baby can laugh like he has never laughed before, and also bats at toys . Anyone in the same situation?

That’s normal actually. My LO did the same, and could grab dangling toys tightly and put them in her mouth by 4 months. It’s always nice to hear early laughter. Heh. The app is only a guide. It’s usually a range of time that these skills develop. Whether slightly earlier/later, as long as they’re within the normal range, it’s good:)