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Review Insights · Google Play

NightWell:Smart Sleep Tracker

C2 INC · 28,003 ratings · ★ 4.2

4.2
★★★★★
28,003 ratings
5 ★
17,232 (62%)
4 ★
5,525 (20%)
3 ★
1,592 (6%)
2 ★
1,873 (7%)
1 ★
1,592 (6%)
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Top complaints - extracted from 18 negative reviews

Recurring phrases mined from 1-2★ reviews. The bigger the percentage, the more users have the same problem. Fix the top 2-3 in your version and you have product-market fit on day one.

1
"phone"
3 negative reviews mention this · 17% of all complaints
★★★★ "This app may be providing my phone number to a third party. After switching the app's language to Japanese and restarting the app, the terms of service screen and agreement button reappeared. About 15 minutes after pressing the button, I re…" - Takayuki Hanada
2
"update"
3 negative reviews mention this · 17% of all complaints
★★★★★ "Used to be great...until this last update. The new interface sucks. Why not keep it simple" - E K
3
"sleep"
3 negative reviews mention this · 17% of all complaints
★★★★ "No sleep cycle graph available, not sure if the tracking works automatically without manually tapping Bedtime, but most likely not (a very important feature missing in all alarm apps). Also cannot swipe to dismiss alarm, instead a simple ta…" - A Google user

📋 All 18 negative reviews

Every 1-2★ review we fetched. Use the copy button to grab them all for your own analysis (paste into ChatGPT/Claude with a prompt like "summarize core user problems, group by theme, ignore bugs, focus on missing features").

★★★★ Takayuki Hanada 4/27/2026
This app may be providing my phone number to a third party. After switching the app's language to Japanese and restarting the app, the terms of service screen and agreement button reappeared. About 15 minutes after pressing the button, I received a call from a hospital that is not in my area. Of course, I have never been there. It is possible that my information is being shared with third parties through advertisements. the android veraion is 16.
★★★★ 真司 4/19/2024
夜に設定しておいたのに翌日の朝にならない事が毎回のようにあって全く使い物になりません。 確実に起きなければならないという方はこのアプリでは無く実物の目覚まし時計が宜しいと思います。
★★★★ Daria Kvochko 3/27/2023 v5.2.0
Cannot use because of some"app overlay" permission, no clear instructions on how to allow this
★★★★ Y N 6/1/2020 v4.2.1
マイクへのアクセスや他のアプリへの優越性を強制したり、胡散臭さが目立ち始めた。むろん使用はもうしない。 問題はデータを何のために使うのかではなく、そのデータが何のために使えてしまうのか。
★★★★ A Google user 8/25/2018 v3.1.18
No sleep cycle graph available, not sure if the tracking works automatically without manually tapping Bedtime, but most likely not (a very important feature missing in all alarm apps). Also cannot swipe to dismiss alarm, instead a simple tap misclick can do it if I don't use e.g. phone shaking instead.
★★★★ A Google user 8/10/2017 v2.39.6
Drains the battery faster than it can be charged.
★★★★ A Google user 6/9/2017 v2.39.6
アラームオフにしても鳴る。
★★★★ A Google user 2/3/2017 v2.39.1
Drained battery fast, so unistalled
★★★★ A Google user 9/3/2016
Crap no sound
★★★★ A Google user 8/18/2016
Useless
★★★★★ E K 5/6/2020 v4.0.5
Used to be great...until this last update. The new interface sucks. Why not keep it simple
★★★★★ A Google user 7/6/2018 v2.40.7
Too bad they took away backup & restore options. I need to restore data
from my old phone which has an older version with offline backup option!
Now it won't let you restore data unless your data are on their "dedicated
cloud server."
★★★★★ A Google user 3/5/2018 v2.40.5
Annoying, pornographic ads placed in spots that you can accidentally click. I had to uninstall. Too bad.
★★★★★ A Google user 1/12/2018 v2.40.5
🚩Inappropriate attempt to skew ratings! I would have given this app more stars, but the very first time I used it, this message popped up: "Will give you Lull Sound Summer Night [lull sounds are a feature of the program and many are locked] if app review with ⭐5!" (can't attach my screenshot but I have one.) It's too bad, because apart from a couple minor issues like the lull sound timer only going up to six hours, this was one of the best sleep data apps I could find, but blatantly offering free gifts in return for five-star ratings (and after only one use!) is really not cool and probably grounds for getting kicked out of the marketplace. I did *not* officially flag the app with Google because I wanted to give the developers a chance to remove this message, but if it is still popping up for future users after, say, 1/31/18, I encourage someone to officially flag these folks. (Scroll down to the way bottom and flag is one of the last links on the app page.) There's a lot of good and useful stuff here but bargaining for ratings like that is unacceptable and doesn't give you an accurate picture of what the app needs anyway. Please remove that pop-up, devs. It's not only against the rules but it really hurts your image.
★★★★★ A Google user 10/6/2017 v2.40.2
Too many permission to grant
★★★★★ A Google user 3/25/2017 v2.39.2
It used to works well with my previous Samsung note4 but it is not compatible with my new OPPO r9. It doesn't ring at all
★★★★★ A Google user 3/21/2016 v2.31
This was a good 4 star before the latest update which came with new poorly placed and thus terribly annoying advertising. I will be deleting unfortunately as a result. Shame
★★★★★ A Google user 11/10/2015 v2.23
UPDATED REVIEW: Its unreliable with the latest update, for me. It mysteriously stops tracking my sleep movements. More often, than not, i have incomplete tracking that stops hours before I actually wake up now. Going back to Sleep for Android for now. Will check back later after this has updated again. OLD REVIEW: Lots of features as well. Switched over from sleep as android app once my trial ended. This has a lot of the same features for free.

Sentiment summary

81%
Positive (4-5★)
6%
Neutral (3★)
12%
Negative (1-2★)

✓ Strong positive sentiment - clone path is harder, users like the existing app.