OneSignal vs Flagsmith
Mobile + web push, email, SMS, and in-app messaging at consumer scale
vs. Open-source feature flags + remote config — SaaS, private cloud, self-host
Pricing tiers
OneSignal
Free
Unlimited mobile push, 10K web push subs, 10K email/mo, 1 journey. GDPR compliant.
Free
Growth
$19/mo + usage. 20K email/mo included, then $1.50/1K. 3 journeys. Advanced in-app.
$19/mo
Professional
Custom. Unlimited volume, 20 journeys, CSV export, prioritized support.
Custom
Enterprise
Custom. Dedicated CSM, SLA, frequency capping, advanced permissions, HIPAA options.
Custom
Flagsmith
Free
$0. 50,000 API requests/mo. 1 team member. Unlimited flags. Community support.
Free
Self-hosted
$0 (OSS). Host yourself via Docker/K8s. Fair-source license (non-compete).
$0 base (usage-based)
Start-up
$40/mo. 1,000,000 API requests/mo. 3 team members. Standard support.
$40/mo
Scale-up
$200/mo. 5,000,000 API requests. 10 team members. Priority support + SLA.
$200/mo
Enterprise
Custom. Unlimited API requests, SSO, SAML, RBAC, audit logs, on-prem.
Custom
Free-tier quotas head-to-head
Comparing free on OneSignal vs free on Flagsmith.
| Metric | OneSignal | Flagsmith |
|---|---|---|
| active journeys | 1 journeys | — |
| email monthly | 10000 emails/mo | — |
| mobile push | Unlimited subscribers | — |
| web push subscribers | 10000 subscribers | — |
Features
OneSignal · 12 features
- A/B Testing — Split testing across push, email, in-app.
- Analytics + Cohorts — Delivery, open, click, conversion metrics + retention cohorts.
- Email — Transactional + marketing email with templates.
- Frequency Capping — Limit message frequency per user.
- In-App Messaging — In-app banners, modals, surveys, carousels triggered by events.
- Intelligent Delivery — Optimize send time per user with ML.
- Journeys — Multi-step automations with branching, delays, actions.
- Live Activities — iOS Dynamic Island + Live Activities.
- Mobile Push — iOS (APNs), Android (FCM/HMS) push notifications.
- Segments — Dynamic audience targeting by tags, location, behavior.
- SMS — Two-way SMS in 200+ countries.
- Web Push — Browser push via service workers (Chrome, Firefox, Edge, Safari, Opera).
Flagsmith · 14 features
- A/B Testing — Multivariate flag splits.
- Audit Log — Full history of flag changes.
- Change Requests — Approval workflow for flag changes.
- Edge API — Global low-latency flag eval.
- Feature Flags — Boolean + multivariate + JSON flags.
- Local Evaluation — Server SDKs eval flags locally — no per-req API call.
- Percentage Rollouts — Gradual traffic ramp.
- Remote Config — Non-boolean config values.
- Role-Based Access — Fine-grained permissions.
- Scheduled Flags — Time-based flag changes.
- Segments — Rule-based targeting.
- Self-Hosting — Docker/Helm install.
- SSO + SAML — Enterprise SSO.
- Webhooks — Outbound event streaming.
Developer interfaces
| Kind | OneSignal | Flagsmith |
|---|---|---|
| CLI | — | Flagsmith CLI |
| SDK | OneSignal Android SDK, onesignal_flutter, OneSignal iOS SDK, @onesignal/node-onesignal, OneSignal Unity SDK, OneSignal Web SDK, react-native-onesignal | flagsmith-android, flagsmith-go, flagsmith-ios, flagsmith-java, flagsmith-js (browser), flagsmith-nodejs, flagsmith-python, flagsmith-ruby |
| REST | OneSignal REST API | Flagsmith REST API |
| OTHER | Outbound Webhooks | Flagsmith Dashboard, Flagsmith Webhooks |
Staxly is an independent catalog of developer platforms. Some links to OneSignal and Flagsmith may be affiliate links — Staxly may earn a commission if you sign up through them, at no extra cost to you. Pricing is verified against vendor pages at publication time — reconfirm before buying.
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