Comparison

Opinion Ninja vs Simple Life Log

Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.

Head to head
About

Opinion Ninja

Earn rewards by sharing your opinions through paid surveys. Redeem points for cash via PayPal or gift cards from popular retailers. Make your voice heard and get paid on the go.

Highlights
  • Take paid surveys on the go
  • Earn rewards for opinions
  • Redeem points for PayPal cash
  • Get gift cards from top retailers
  • Choose survey length and reward
Features
Read full description

You MUST have an existing membership and email with a market research panel associated with Opinion Ninja! Getting started is easy. Download the app and log in with the same email address you used to sign up to your market research panel associated with Opinion Ninja. OpinionNinja is the top place to get paid for your opinions. Take hundreds of paid surveys for money on the go, wherever you are. Choose the ideal survey length and reward amount from hundreds of available opportunities on your schedule. Make a difference with your opinion with paid surveys. TAKE SURVEYS The OpinionNinja App allows you to get paid for giving your opinion and making money on the go or at home with your smartphone or tablet. Complete surveys on various important topics and make your opinion count. GET CASH AND FREE GIFT CARDS OpinionNinja has hundreds of Gift Cards available with the leading retailers! Redeem your Reward Points for PayPal cash or gift cards at Amazon, Apple, Target, Mastercard, Walmart, Starbucks, Uber, and many more. Cash out your rewards for gift card values starting at just $1. [:mav: 1.1.34]

About

Simple Life Log

Features
Read full description

Simple Life Log helps you record your daily activities by date, item, and memo. All data stays only on your device—no account required, no cloud sync. A straightforward way to keep a personal lifelog with privacy in mind. ■ KEY FEATURES • Record by date, item, and memo Tap a date and an item (e.g. Exercise, Reading, Meals), add an optional memo, and save. Your log is stored locally on your device. • No account, no server Everything is saved only on your phone or tablet. We do not collect or upload your data. • Ready-made and custom items Use built-in items like Exercise, Workout, Meals, Cooking, Reading, Meditation, and more. You can also add, edit, or hide items to match your lifestyle. • Calendar view See your logs on a calendar. Tap a day to add or view entries. • Search by period and item Search logs by period (e.g. last week, this month, last year) or choose a custom date range. Filter by a single item to see when you did that activity. • Available in English and Japanese The app and store listing can be shown in your language. ■ HOW TO USE • Home Today’s log and quick access to add new entries. Tap an item to log it for today with an optional memo. • Calendar Browse logs by month. Tap a date to add or see logs for that day. • Data Manage your items: add new ones, edit names and colors, or move items to “deleted” (they stay available for past logs). • Search Set a period (preset or custom range) and optionally pick one item. Results are shown as a list by date. Only the result area scrolls for easy reading. ■ DATA & PRIVACY All data is stored only on your device using local storage (SQLite). We do not send your logs, items, or memos to any server. For more details, see the in-app privacy policy link. ■ SUPPORT If you have questions or feedback, please contact us via the email in the app’s privacy policy or store listing. Thank you for trying Simple Life Log.

Screenshots

Opinion Ninja4 screens
Simple Life Log4 screens

Verdict

The call

The clearest difference is update cadence: Simple Life Log at every 2 days against Opinion Ninja's every 5 weeks. Simple Life Log also leads on iOS requirement (13.0 vs 15.6). On price, ads, in-app purchases and device support there is nothing between them.

Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS

CostPrice · In-app purchases · Ads · Monetization

Both are free to download. Neither carries in-app purchases, so what you see is what you pay.

UpkeepUpdate frequency

Opinion Ninja ships an update every 5 weeks, Simple Life Log every 2 days. The most recent releases landed on November 3, 2026 and October 31, 2026 respectively.

Scorecard2 real differences · 8 level
Opinion Ninja versus Simple Life Log: the parameters behind the verdict, then further details
ParameterOpinion NinjaSimple Life Log
PriceFreeFree
Rating4.6 (57 ratings) — better—
Positive reviews80.0% of reviews—
Number of ratings57 — better—
Update frequencyEvery 5 weeksEvery 2 days — better
AdsYesYes
In-app purchasesNoNo
MonetizationAd-supported—
DevicesiPhone, iPad, iPodiPhone, iPad, iPod
Requires iOS15.613.0 — better
Further details — not scored
Size59 MB30 MB
Age rating17+4+
DeveloperSample NinjaRYOJI NAKASHIMA

In-app purchases

None

Opinion Ninja

No in-app purchases

None

Simple Life Log

No in-app purchases

Questions

Is Opinion Ninja free?
Opinion Ninja is free to download, with no in-app purchases.
Is Simple Life Log free?
Simple Life Log is free to download, with no in-app purchases.
Do Opinion Ninja or Simple Life Log have ads?
Both Opinion Ninja and Simple Life Log show ads.
Which is updated more often, Opinion Ninja or Simple Life Log?
Opinion Ninja ships an update every 5 weeks, and Simple Life Log every 2 days. Most recently, Opinion Ninja was updated on November 3, 2026 and Simple Life Log on October 31, 2026.

Other comparisons