Regional Provider Comparison
RoadGuard vs Smart Start: Which IID Is Better in TX, OH & TN?
RoadGuard Interlock is a strong regional provider in Texas, Ohio, and Tennessee. Here's how it compares to Smart Start on cost, app quality, and customer support.
Our Pick
Smart Start
Smart Start edges out RoadGuard on app quality, overall rating, and customer support. However, RoadGuard's lower monthly cost and regional expertise make it a competitive choice in TX, OH, and TN.
At a Glance
Smart Start
Winner- Best mobile app in the industry
- Higher overall customer rating
- Available if you relocate out of state
RoadGuard Interlock
Runner-up- Lower monthly cost than Smart Start
- Regional expertise in TX, OH, TN
- Not available outside these 3 states
Feature-by-Feature Comparison
| Feature | Smart Start | RoadGuard |
|---|---|---|
| Regional Coverage | All 50 states | TX, OH, TN |
| Monthly Cost | $70-90 | $65-85 |
| Installation | $0-99 | $0-75 |
| Customer Rating | 4.4/5 | 4.2/5 |
| Mobile App | Excellent (4.5+) | Good |
| 24/7 Support | 24/7 (highly rated) | 24/7 |
| Calibration | Included | Included |
| Regional Expertise | General | TX/OH/TN specialist |
Cost — Where RoadGuard Wins
| Cost Type | Smart Start | RoadGuard |
|---|---|---|
| Installation | $0-99 | $0-75 |
| Monthly Lease | $70-90 | $65-85 |
| Calibration | Included | Included |
| 12-Month Estimate | $890-1,179 | $840-1,095 |
Edge: RoadGuard — typically $50-100 cheaper per year in these three states.
Mobile App — Where Smart Start Wins
Smart Start has the best IID mobile app available — consistently rated 4.5+ on iOS and Android. RoadGuard's app is functional but doesn't match Smart Start's polish or feature set. If the app experience matters to you, choose Smart Start.
The Bottom Line
Choose Smart Start if:
- The mobile app experience matters to you
- You want the highest-rated customer support
- You may relocate out of TX, OH, or TN
Choose RoadGuard if:
- You want to save $50-100/year on total cost
- There's a RoadGuard location convenient to you
- You're staying in TX, OH, or TN for your full requirement period
Other Comparisons
Sources
Comparison based on provider websites, state DMV data, and customer reviews as of March 2026.Last updated: March 20, 2026
- 01Texas DPS - Ignition Interlock (Regulatory Services Division)dps.texas.gov · Texas vendor standards and device approval
- 02Texas DPS - Approved Ignition Interlock Devices (PDF)dps.texas.gov · Texas approved device models, including Smart Start
- 03Ohio Adm.Code 4501-45-04 - Certification requirements for ignition interlock devicescodes.ohio.gov · Ohio device certification and monitoring rules
- 04Tennessee Department of Safety - Ignition Interlocktn.gov · Tennessee interlock program and provider search
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