If you want better durability
Choose Levoit EverestAir. It scores 4.7 vs 1.5 for durability, with a 4.5 overall score.
Alen BreatheSmart 35i Air Purifier Review
Bottom Line
Choose the Alen BreatheSmart 35i for quiet small-room air cleaning, strong sensors, and smart controls. Skip it for large rooms, tight budgets, or if filter costs and rattling risk worry you.
Best for
Best for bedrooms, studios, small living areas, pet homes, and allergy-sensitive users who want quiet operation plus detailed air-quality monitoring.
Not for
Not for buyers expecting large-room performance, low ownership costs, or a heavy-duty build without any risk of rattling complaints.
Verdict
The Alen BreatheSmart 35i earns its strongest praise as a compact, quiet purifier with unusually useful sensing and app features. Expert tests and many customers report better air quality, odor reduction, responsive auto mode, and easy controls, especially in bedrooms, studios, and smaller living spaces. The tradeoff is cost: both upfront price and replacement filters are frequent concerns, and coverage evidence points toward small rooms rather than the largest advertised spaces. Build feedback is also split, with some praise for fit and seal quality but several complaints about plastic feel, rattling, or defects. Overall, it is a polished small-room purifier when quiet operation and monitoring matter more than maximum value.
Feature Scorecards
Summary
49 reviewed features-
Very positive 4.5-5.026 (53%)
-
Positive 3.5-4.414 (29%)
-
Neutral 2.5-3.47 (14%)
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Negative 1.5-2.42 (4%)
Pros highlights
-
Noise feedback is strongly positive overall, but a few customers report weird sounds or rattling.
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Overall satisfaction is high across experts and most customers, offset by a few sharp negative experiences.
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Most reviewers say the purifier improves air quality or works well, though one customer reported poor cleaning performance.
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Odor reduction is one of the strongest customer-backed benefits, especially for pets, smoke odor, cooking, and basement smells.
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Real-time monitoring is a major strength, with repeated praise for alerts, app graphs, and color feedback.
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Setup and controls are repeatedly described as easy, intuitive, or plug-and-use.
Cons highlights
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Filter replacement cost is one of the clearest concerns, though a few customers accept it because replacements are less frequent.
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Room coverage is best for small rooms; reviewers repeatedly caution against expecting large-room performance.
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Build quality is split: HouseFresh praises it, while Live Science and customers cite plastic, cheap feel, or rattling.
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Value is mixed: many think it is worth buying, while experts and one customer stress high upfront and ownership costs.
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Power consumption is acceptable in expert testing but one customer complains it raises the bill.
Compared With Category Average
Compared with other Air Purifiers, this product is above average in remote control, smart features, handle design, near average in overall satisfaction, air purification performance, below average in durability, dust removal, reliability.
Comparison summary
49 compared features-
Above average 0.4+ pts higher26 (53%)
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Same as average within 0.3 pts14 (29%)
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Below average 0.4+ pts lower9 (18%)
Largest category differences
| Attribute | This product | Category average | Difference |
|---|---|---|---|
| durability | 1.5 | 3.3 | -1.8 |
| remote control | 4.5 | 2.7 | +1.8 |
| smart features | 5.0 | 3.3 | +1.7 |
| handle design | 5.0 | 3.3 | +1.7 |
| filter availability | 5.0 | 3.5 | +1.5 |
| dust removal | 2.9 | 4.3 | -1.4 |
| warranty coverage | 5.0 | 3.6 | +1.4 |
| air quality sensor accuracy | 5.0 | 3.7 | +1.3 |
Consider This Instead
If you want better power consumption
Choose Shark NeverChange Air Purifier, HP152. It scores 4.8 vs 3.0 for power consumption, with a 4.1 overall score.
If you want better customer support
Choose Shark HP102. It scores 5.0 vs 2.5 for customer support, with a 4.1 overall score.
If you want better pollen removal
Choose Levoit Vital 200S. It scores 4.7 vs 3.6 for pollen removal, with a 4.4 overall score.
Compared in Reviews
Products reviewers directly compared with this model, grouped into quick takeaways.
- Cheaper: price and monitoring depth The BlueAir is cheaper, but its air-quality monitoring is less in-depth.
- Cheaper: pet-friendly design and price The Levoit Vital 200S is presented as a cheaper pet-friendly alternative.
AirFanta 3Pro
- Better: small-room cleaning performance The 35i was outperformed by the AirFanta 3Pro in expert particle testing.
FAQ
Is the Alen BreatheSmart 35i good for bedrooms?
Yes. Reviewers repeatedly praise its quiet operation, compact footprint, sleep-friendly lighting, and better nighttime breathing or sleep.
Does it remove odors?
Yes, odor reduction is one of the strongest customer themes, especially for pets, cooking, basement smells, and smoke odor.
Is it good for large rooms?
The evidence points to small-room use. Expert reviewers recommend sizing down from the largest coverage claims if you want stronger air changes.
Are the filters expensive?
Yes. Several reviews mention costly filters, though some customers feel the longer replacement interval makes the cost easier to accept.
How good is the app and smart monitoring?
The app, sensors, schedules, alerts, and real-time monitoring are major strengths, but a few users report app sign-up or registration problems.
Is it quiet?
Most evidence says it is very quiet, including expert testing. A minority of customers report weird sounds or rattling after use.
Sample Expert Reviews We Analyzed
These are a few of the reviews included in our analysis.
Video Reviews
YouTube - AppMyHome
- Review score
- 4.8
Article Reviews
livescience.com
- Review score
- 4.5
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