Comparison

Coal 2 Solar vs Soul Diary

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

Head to head
About

Coal 2 Solar

Features
Read full description

Coal to Solar is your smart solution for a cleaner, greener Mongolia. Designed specifically for the ger district community, this app helps households track their electricity usage, monitor the impact of their solar panels and electric heaters, and contribute to solving one of Mongolia's most pressing issuesβ€”air pollution. By transitioning from burning coal to solar energy and electric heating, you not only reduce harmful emissions but also earn carbon credits verified by Gold Standards. Track your progress, save on energy costs, and join the movement toward a sustainable future. Download Coal to Solar today and be part of URECA’s mission to transform Mongolia’s energy landscape and create healthier communities for generations to come.

About

Soul Diary

Features
Read full description

Your exclusive corner for recording the inner world. There are a variety of wallpapers that can be changed as you like, creating diverse creative atmospheres. The "Sentence of the Day" is like a bright light for the soul, bringing wisdom and insights. The convenient voice input allows you to capture the sparks of your thoughts instantly. Practical tools such as text editing and classification tags help you organize your diaries efficiently. No login is required, so you don't have to worry about privacy issues. We will never steal your information and will wholeheartedly safeguard your inner world, accompanying you to freely write down the bits and pieces of life and the touches of your soul. I. Personalized Interface There is a rich collection of wallpapers that can be chosen at will. They come in diverse styles to match your mood. The operation interface is simple and intuitive, making it easy to use. II. Content Assistance The "Sentence of the Day" prompts you to think deeply. Profound sentences inspire you to record your thoughts in a more profound way. Writing topics and emotional tags help you spark inspiration. III. Convenient Input The language input feature can accurately recognize multiple languages. Converting voice into text is highly efficient and convenient. When inputting manually, there are intelligent word association and error correction functions. IV. Management and Privacy Diaries can be managed and classified in multiple dimensions. Customized tags make it convenient to retrieve them. Diaries are stored in an encrypted way and no login is required, strictly protecting your privacy.

Screenshots

Coal 2 Solar3 screens
Soul Diary4 screens

Verdict

The call

The clearest difference is ads: Coal 2 Solar at none against Soul Diary's shown. Soul Diary's advantage is update cadence (fortnightly vs monthly) and iOS requirement (13.0 vs 16.4). On price, in-app purchases and device support there is nothing between them.

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

CostPrice Β· In-app purchases Β· Ads Β· Monetization

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

UpkeepUpdate frequency

Coal 2 Solar ships an update monthly, Soul Diary fortnightly. The most recent releases landed on November 4, 2026 and October 30, 2026 respectively.

Scorecard3 real differences Β· 3 level
Coal 2 Solar versus Soul Diary: the parameters behind the verdict, then further details
ParameterCoal 2 SolarSoul Diary
PriceFreeFree
Update frequencyMonthlyFortnightly β€” better
AdsNo β€” betterYes
In-app purchasesNoNo
DevicesiPhone, iPadiPhone, iPod
Requires iOS16.413.0 β€” better
Further details β€” not scored
Size45 MB48 MB
Age rating4+4+
DeveloperUrecaHONG KONG GUANGSHANG TRADING CO.,LIMITED

In-app purchases

None

Coal 2 Solar

No in-app purchases

None

Soul Diary

No in-app purchases

Questions

Is Coal 2 Solar free?
Coal 2 Solar is free to download, with no in-app purchases.
Is Soul Diary free?
Soul Diary is free to download, with no in-app purchases.
Do Coal 2 Solar or Soul Diary have ads?
Soul Diary shows ads; Coal 2 Solar does not.
Which is updated more often, Coal 2 Solar or Soul Diary?
Coal 2 Solar ships an update monthly, and Soul Diary fortnightly. Most recently, Coal 2 Solar was updated on November 4, 2026 and Soul Diary on October 30, 2026.

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