Compare AI tools

	GitHub Copilot B	Cartesia S	OpenRouter S	Gamma A
Tagline	Microsoft/GitHub's autocomplete. Deep VS Code + JetBrains integration.	Ultra-low-latency voice. Built for realtime agents.	One API, every model. Pay-as-you-go, no subscriptions.	AI slide decks that don't look AI-generated.
Category	Coding	Voice	Dev Platform	Productivity
Pricing	Free (limited) + $10/mo Pro + $19/mo Business	Free tier + usage-based API	Pay per token — model-dependent	Free + $10-$20/mo
Best for	Teams with GitHub already. Devs who don't want to change IDEs.	Developers building voice agents, phone bots, interactive apps.	Developers experimenting across models. Apps that want fallback logic.	Pitch decks, proposals, internal presentations — fast.
Strengths	Great enterprise story Works in your existing IDE Chat + autocomplete	< 90ms latency — the fastest in the market Sonic model sounds natural Developer-friendly API	300+ models from one endpoint Automatic fallbacks between providers No subscription — just pay what you use	Strong templates Decks, docs, webpages Doesn't look generic
Weaknesses	Less agentic than Cursor/Claude Code Model quality varies	Fewer voices than ElevenLabs Less consumer-facing brand	Slight markup over direct API Some provider features not exposed	Locked into Gamma's format Export quality varies
Kai's verdict	B-tier. Solid for autocomplete but the category moved past it. Pick Cursor unless you can't.	S-tier for realtime. If latency matters more than voice catalog, start here.	S-tier for model-shopping. I use this for every prototype before committing.	A-tier. Best of a boring category. Use it for first drafts, then edit in Keynote if high-stakes.
Link	Open →	Open →	Open →	Open →