Compare/ElevenLabs Conversational AI Phone Calling API vs Kampala

AI tool comparison

ElevenLabs Conversational AI Phone Calling API vs Kampala

Which one should you ship with? Here is the side-by-side panel verdict, pricing read, reviewer split, and community vote comparison.

E

Developer Tools

ElevenLabs Conversational AI Phone Calling API

Deploy voice agents on real phone calls with sub-500ms latency

Ship

100%

Panel ship

Community

Paid

Entry

ElevenLabs has launched an outbound and inbound phone calling API built on its Conversational AI platform, enabling developers to deploy voice agents that handle real phone calls with sub-500ms latency. The API supports both triggering outbound calls programmatically and receiving inbound calls, with the voice quality and naturalness ElevenLabs is known for. It is aimed at developers building customer service automation, sales dialers, appointment reminders, and other telephony-powered workflows.

K

Developer Tools

Kampala

MITM proxy that reverse-engineers any app into a stable, callable API

Ship

75%

Panel ship

Community

Free

Entry

Kampala, built by Zatanna AI (YC W26), is a macOS proxy tool that sits between your applications and the internet, intercepts every HTTP/HTTPS request, and automatically reverse-engineers the underlying API. It traces authentication chains — tracking tokens, cookies, and session state — and replays flows on demand, preserving original TLS fingerprints so services can't distinguish API calls from the real app. The key insight is that almost every app that lacks a public API still has a private one — and it's usually more stable than the UI. Kampala targets automation engineers, QA teams, and AI agent builders who need reliable machine-readable access to apps that haven't opened their APIs. Setup is a local MITM cert install; no cloud proxy involved. Currently macOS-only with a Windows waitlist. The team emerged from YC's Winter 2026 batch with backing from Y Combinator. Pricing is in early access, with a free tier planned for solo developers and paid plans for teams building production automations.

Decision
ElevenLabs Conversational AI Phone Calling API
Kampala
Panel verdict
Ship · 4 ship / 0 skip
Ship · 3 ship / 1 skip
Community
No community votes yet
No community votes yet
Pricing
Usage-based on ElevenLabs platform credits; scales with call volume and character usage
Free (early access)
Best for
Deploy voice agents on real phone calls with sub-500ms latency
MITM proxy that reverse-engineers any app into a stable, callable API
Category
Developer Tools
Developer Tools

Reviewer scorecard

Builder
82/100 · ship

The primitive here is clean: a REST endpoint that initiates or receives a phone call and patches it into a stateful conversational AI agent — no Twilio-wrangling, no separate STT/TTS pipeline assembly. The DX bet is that ElevenLabs handles the telephony layer (SIP, PSTN, latency buffering) so you don't have to glue together four vendors. The moment-of-truth test is whether you can kick off an outbound call with one API call in under 10 minutes, and based on the documented structure it looks like you can. The weekend alternative — duct-taping Twilio + Deepgram + ElevenLabs TTS + an LLM yourself — is genuinely painful enough that this wrapper earns its existence.

80/100 · ship

This is the tool I've been building in-house at three different companies and never had time to productize properly. The auth chain tracing alone — tracking token refresh flows and session state automatically — would have saved me hundreds of hours. If it works as advertised, it's an instant ship for anyone doing integration work.

Skeptic
75/100 · ship

Direct competitors are Twilio Voice Intelligence, Bland.ai, and Retell AI — all shipping roughly the same product right now, so ElevenLabs is on-time not early. The specific scenario where this breaks is high-concurrency enterprise deployments where you need SLA guarantees, HIPAA BAAs, and custom PSTN routing — ElevenLabs is not that company yet. What kills this in 12 months is not a competitor but OpenAI or Google shipping native realtime phone-call APIs bundled with their model subscriptions, commoditizing the voice layer entirely. That said, ElevenLabs has the best voice quality in the market right now, and voice quality is the one thing that actually matters for call completion rates — that's a real differentiator, not a marketing claim.

45/100 · skip

Terms of service violations are a real concern here. Most apps explicitly prohibit automated access through their private APIs, and companies like LinkedIn and Instagram have sued over exactly this pattern. The MITM cert requirement also opens a broad attack surface. Wait for a clearer legal stance before building production systems on this.

Founder
78/100 · ship

The buyer is a mid-market SaaS team or agency that currently pays Twilio plus a separate TTS vendor plus engineering time to maintain the glue — this collapses three line items into one and comes from a budget that already exists. The moat is ElevenLabs' proprietary voice models, which are genuinely ahead on naturalness and are hard to replicate quickly; the platform lock-in comes from voice clones and agent configuration living in ElevenLabs' system. The real stress test is when OpenAI's realtime API gets cheaper and ships telephony natively — at that point ElevenLabs needs the voice quality gap to still be measurable, which is a bet on a moving target. Usage-based pricing aligned to call volume is correct architecture here; the danger is enterprise customers churning once they can negotiate volume deals with a bigger platform player.

No panel take
Futurist
80/100 · ship

The thesis is falsifiable: within three years, the majority of first-touch business phone interactions will be handled by voice AI, and the bottleneck will shift from 'can we build this' to 'can we build voice agents that sound indistinguishable from humans.' ElevenLabs is betting that voice quality, not telephony infrastructure, is the scarce resource — and that owning the voice layer means owning the agent layer by extension. The second-order effect that matters most here is not call center displacement but the emergence of a new class of micro-businesses that could never afford human phone staff — a solo consultant running 500 outbound qualification calls a day is a new behavior this infrastructure makes possible. The dependency that has to not happen is Google or OpenAI bundling sub-500ms phone calling into their existing developer platforms, which is a real risk given Gemini Live and GPT-4o realtime are already trending that direction.

80/100 · ship

The long-term story here is about AI agents needing reliable access to every app humans use. We can't wait for every SaaS to ship an official API. Tools like Kampala are how AI agents will integrate with the existing software ecosystem for the next five years, until MCP-style universal interfaces catch up.

Creator
No panel take
80/100 · ship

For social media automation and cross-platform content workflows this is a game-changer. Building automations for platforms with limited or expensive APIs has always required fragile browser scraping — having a stable API layer extracted from the real app traffic is a much better foundation.

Weekly AI Tool Verdicts

Get the next comparison in your inbox

New AI tools ship daily. We compare them before you waste an afternoon.

Bookmarks

Loading bookmarks...

No bookmarks yet

Bookmark tools to save them for later