Facts read November 7, 2026
Ably vs Cached polling (no realtime service)
Ably is Cuely's default realtime pick when your description doesn't favor either one: reliable pub/sub and presence, billed by users rather than messages. Pick Cached polling (no realtime service) if you care most about viral traffic spikes.
Side by side
| Fact | Ably | Cached polling (no realtime service) |
|---|---|---|
| What it is | Hosted pub/sub messaging with presence, priced by monthly active users. | Clients re-fetch one results endpoint every few seconds, and the host caches its answer so every player shares it. |
| Free plan | Free: up to 500 monthly active users. | No service to sign up for. On Vercel, a function response with Cache-Control: s-maxage is served from the CDN, and a cached response doesn't run the function; on Cloudflare Workers, cache the answer with the Cache API, and each poll is a Worker request. |
| Paid from | Pro: from $29/month (1,000 MAU), billed annually. | Not stated |
| At 1,000 users | $29/month | $0/month |
| Open source | No | No |
| Self-hostable | No | Yes |
| Best for | Live notifications and chat; Apps with many messages per user | Live vote percentages and leaderboards; Traffic that spikes when something is shared; Staying on one bill |
| Watch out | The free plan stops at 500 monthly active users; Pro is billed annually. | Players see numbers up to the cache time old (a few seconds); use a push service for chat, cursors or fast multiplayer. |
Where they differ
The published scores, from −3 to +3, that decide which one Cuely picks for each need.
| Need | Ably | Cached polling (no realtime service) |
|---|---|---|
| traffic comes in viral spikes | −2 Billed by monthly active users: Free stops at 500, and one viral day can bring tens of thousands. | +3 Every player reads the same cached answer, so a viral day adds cheap cached requests, not connections or messages. |
| realtime features | +2 Pub/sub and presence with delivery guarantees. | −1 Updates every few seconds rather than instantly: fine for crowd numbers, not for presence, chat or shared editing. |
| keep costs as low as possible | 0 No particular strength here. | +2 No extra vendor or bill. |
| votes, scores, leaderboards or streaks (many writes to the same numbers) | 0 No particular strength here. | +2 Fits tallies and leaderboards that only need to be a few seconds fresh. |
| high volume | +1 Billing by users, not messages, suits chatty apps. | 0 No particular strength here. |
| native iOS or Android app | +1 SDKs for iOS, Android and React Native. | 0 No particular strength here. |
Sources: Ably pricing (read November 7, 2026), Cached polling (no realtime service) pricing (read November 9, 2026). No vendor pays for placement.