Sahha vs Terra API
Behavioral Intelligence vs Raw Data Aggregation
Executive Summary
Sahha
Best For: EAP, mental health, insurance, fitness apps requiring predictive insights
Key Strength: Behavioral intelligence with 5 health scores (sleep, activity, mental wellbeing, wellbeing, readiness)
Unique Feature: Works with smartphones alone (no wearable required)
Data Retention: 3 months included
Pricing: Per-user/month (predictable)
Terra
Best For: Multi-device raw data aggregation
Key Strength: 90+ direct device integrations
Unique Feature: Preserves raw device data without transformation
Data Retention: Pass-through only (no storage)
Pricing: Credit-based ($399/mo + usage)
Feature-by-Feature Comparison
1. Core Approach
Sahha
Behavioral intelligence platform that transforms raw sensor data into actionable insights. Generates health scores, identifies patterns, detects early warning signs of declining wellness.
- 5 health scores (sleep, activity, mental wellbeing, wellbeing, readiness)
- Behavioral archetypes (night owl, early bird, consistent sleeper)
- Predictive detection: 3-5 days before subjective awareness
- Validated with University of Otago research (4,500 participants)
Terra
Data aggregation platform that normalizes raw health data from multiple devices into standardized format. Provides access to device metrics without additional processing or intelligence.
- Raw metrics: steps, heart rate, sleep duration, calories
- Standardizes units and JSON format
- Does not augment or interpret data
- Webhook pass-through architecture
2. Device Coverage
Sahha
Platform API Strategy: 300+ devices via HealthKit (iOS) and Health Connect (Android)
- All wearables that sync to Apple Health or Google Fit
- Apple Watch, Garmin, Fitbit, Whoop, Oura, Polar
- Smartphone sensors (accelerometer, gyroscope)
- No wearable required - works with phone alone
- Inclusive: reaches 4.88B smartphone users
Terra
Direct Integration Strategy: 90+ direct device connections
- Individual OAuth integrations per device
- Garmin, Fitbit, Whoop, Oura, Polar, Suunto
- Peloton, Strava, Zwift
- HealthKit and Google Fit also supported
- Exclusive: requires wearable ownership
3. Data Intelligence
Sahha
Intelligence Layer Included:
- Sleep Score: Quality, regularity, efficiency, debt
- Activity Score: Movement patterns, sedentary time
- Mental Wellbeing: App usage, screen time, behavioral patterns
- Readiness: Recovery state, workout capacity
- Wellbeing: Overall health status composite
Output Example: "Sleep quality declining 15% over 2 weeks, stress markers elevated, burnout risk: moderate"
Terra
Raw Data Only:
- Steps: Count, distance, calories
- Heart Rate: BPM, resting HR, HRV
- Sleep: Duration, start/end time, stages (if device provides)
- Workouts: Type, duration, calories, distance
- Body: Weight, BMI, body fat %
Output Example: "7,842 steps, 7h 23m sleep, 68 bpm average HR, 2 workouts"
4. Data Retention & Storage
Sahha
3 Months Included:
- Historical data stored for longitudinal analysis
- Enables trend detection and pattern recognition
- Baseline establishment for personalized insights
- HIPAA & GDPR compliant storage
- Query historical data via REST API
Why This Matters: Behavioral intelligence requires historical context. Can't detect "declining sleep quality" without weeks of baseline data.
Terra
Pass-Through Architecture:
- No data storage - webhook delivery only
- Your backend must capture and store all data
- Real-time updates pushed to your webhook
- Historical data available via initial sync
- You build storage infrastructure
Why This Matters: Lower vendor lock-in, but requires building your own database, backup, retention policies, and compliance infrastructure.
5. Pricing Structure
Sahha
Per-User Monthly:
- Predictable per-user pricing
- Scales with user count
- No overage charges for API calls
- All 5 health scores included
- Webhook events included
- 3-month data retention included
Example: 1,000 users = 1,000 × per-user price per month (contact for pricing)
Terra
Credit-Based Usage:
- Base: $399/month includes 100,000 credits
- Credits reset monthly (no rollover)
- Additional usage billed monthly
- Tiered pricing: more credits = cheaper per credit
- Usage spike protection (first 6 months)
- Enterprise plans available
Example: Complex to predict - depends on data volume, API calls, webhook frequency
6. Integration Complexity
Sahha
Timeline: 2-4 weeks typical
- Week 1: SDK integration, permissions, auth setup
- Week 2: Webhook processing, data handling
- Week 3: UI implementation, score display
- Week 4: Testing, refinement, production
Common Issues: Webhook signature verification (2 hrs), profile authentication (4-6 hrs), field naming (mental_wellbeing vs mentalWellbeing)
Terra
Timeline: 1-2 weeks for basic setup
- Week 1: Authentication flow, widget integration
- Week 2: Webhook processing, database design
- Ongoing: Build intelligence layer (if needed)
Common Issues: No data storage requires robust backend, intelligence layer requires data science team ($45K/month estimated)
7. Use Case Fit
Sahha
Ideal For:
- ✓ Employee wellness & EAP programs
- ✓ Mental health monitoring
- ✓ Insurance behavioral underwriting
- ✓ Fitness app personalization
- ✓ Supplement recommendations
- ✓ Burnout detection
- ✓ Sleep quality programs
Not Ideal For: Raw device data collection without insights, research requiring unprocessed sensor data
Terra
Ideal For:
- ✓ Multi-device data aggregation
- ✓ Building custom intelligence layers
- ✓ Raw data research studies
- ✓ Dashboard/analytics platforms
- ✓ Integration with existing data science teams
Not Ideal For: Startups without data science resources, apps needing predictive insights out-of-box, smartphone-only use cases
Which Should You Choose?
Choose Sahha If:
- You need behavioral insights, not just data
- Your use case is mental health, EAP, or burnout prevention
- You want inclusive coverage (smartphone + wearable users)
- You don't have a data science team
- You need longitudinal data retention
- You want predictable per-user pricing
- You're building for global markets (developing countries)
- Time-to-market matters (4 weeks vs 6+ months)
Choose Terra If:
- You need raw, unprocessed device data
- You have data science resources to build intelligence
- You want control over data processing and storage
- Your users primarily own wearables
- You need specific device integrations not via platform APIs
- You're building a dashboard/analytics platform
- Credit-based pricing fits your cost model
- You're conducting research requiring raw sensor data
Hybrid Approach
Some organizations use both: Terra for raw data collection from specific devices, Sahha for behavioral intelligence and smartphone users. This provides comprehensive coverage while maintaining flexibility.
Real-World Impact
Scenario: Corporate Wellness Program (5,000 employees)
With Sahha
- Coverage: 4,500 employees participate (90% - smartphone-based)
- Insights: Immediate behavioral intelligence
- Detection: 127 employees flagged with declining sleep quality
- Intervention: Proactive EAP outreach 2 weeks before crisis
- Cost: Predictable per-user pricing
- Time to Value: 4 weeks
With Terra
- Coverage: 1,200 employees participate (24% - wearable owners only)
- Insights: Requires building intelligence layer
- Detection: Not possible without data science team
- Intervention: Reactive only (after visible behavior change)
- Cost: $399/mo + credits + $45K/mo data science team
- Time to Value: 6+ months
Outcome: Sahha provides 3.75× higher participation, predictive insights, and $540K annual savings by not requiring data science team.
Technical Specifications
| Feature | Sahha | Terra |
|---|---|---|
| Authentication | Profile-based tokens, OAuth 2.0 | Widget-based, OAuth per device |
| Webhooks | HMAC-SHA256 signatures, 3 event types | Standard webhooks, device-specific payloads |
| REST API | Profile queries, historical data | Device connections, user management |
| SDKs | iOS, Android, Flutter, React Native, Web | iOS, Android, React, React Native |
| Data Format | Standardized health scores + biomarkers | Device-native JSON (normalized) |
| Update Frequency | 2-5 minutes typical (sub-minute possible) | Real-time via webhooks |
| Compliance | HIPAA, GDPR | HIPAA, GDPR |
| Rate Limits | Undocumented (discover in production) | Credit-based (transparent) |
The Bottom Line
Sahha and Terra solve different problems. Terra aggregates raw data from 90+ devices - excellent if you have the resources to build intelligence layers and primarily serve wearable owners. Sahha provides behavioral intelligence from day one, works with smartphones alone, and includes 3-month data retention - making it the clear choice for EAP, mental health, insurance, and fitness applications that need predictive insights, not just historical metrics.
The math is compelling: Sahha reaches 8.5× more users (smartphone + wearable vs wearable-only), provides intelligence without a $540K/year data science team, and enables proactive intervention 3-5 days before users notice declining wellness.
For most applications: Start with Sahha. The behavioral intelligence, inclusive coverage, and predictable pricing make it the pragmatic choice. Consider Terra only if you specifically need raw device data and have data science resources to process it.