Pika has carved out a niche as the playful, social-first AI video generator. ZSky AI offers free unlimited AI video as part of a broader image-and-video toolkit. They overlap in the middle but the experiences are different. I've been generating AI video on both for months. This is the breakdown for someone trying to figure out which fits their workflow. Quick Comparison ZSky AI Pika Cost Free, unlimited Free tier (limited), $10–$70/mo paid Sound No (visuals only) Yes (sound on supported plans) Lip sync Limited Yes (signature feature) Image-to-video Yes Yes Text-to-video Yes Yes Effect library Prompt-based Curated effects (e.g. "explode," "melt") Max clip length ~5–10s typical ~5–10s (extendable on paid) Latency ~30–60s ~1–2 min Mobile Yes Yes Where Pika Wins Honest list — Pika has built specific things really well. Lip sync. Pika's lip-sync feature is one of the cleanest on the market. Upload an image of a face, give it audio, get a clip where the face speaks. ZSky doesn't have a true lip-sync product.…