Apart from storage, is there anything else I can buy?

Yes — add-on packs, and right now those are WhatsApp credits. You can buy 200 credits for ₹100, 1,000 for ₹500, or 2,000 for ₹1,000, all one-time payments that stay on your account for life and don't interfere with your main subscription. These credits are what fuel the WhatsApp guest notifications, since each message costs Snaptide a small amount to send. If you shoot a lot of events and rely on WhatsApp to tell guests their photos are live, an add-on pack is worth keeping in mind.