Comparison

Pillowbook vs Sidera

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

Head to head
About

Pillowbook

Record your dreams and receive personalized interpretations based on a vast library of symbols and your unique personal history. This app builds a knowledge graph of your dream elements to reveal recurring themes and connections.

Highlights
  • Dream journaling
  • Personalized dream interpretation
  • Symbol library
  • Knowledge graph of dream elements
  • Theme and connection analysis
Features
Read full description

Pillowbook is a beautiful dream journal and personal dream decoder. Wake up, jot down whatever fragments of your dreams your sleeping mind leaves behind, and see a deep interpretation drawn from a built-in library of dream symbols and tuned to who you actually are. Most dream meaning apps hand you a generic one-size-fits-all dictionary. Pillowbook is different: every symbol, emotion, person, and place you log becomes a node in your own growing knowledge graph, so you can see which themes and people keep returning across nights and which symbols bind together to reveal the complex inner workings of your psyche.

About

Sidera

This app analyzes your birth moment using both Korean Saju and Western astrology, offering detailed interpretations and comparisons. It allows you to explore raw chart data, compare astrological readings with MBTI types, and assess compatibility with others.

Highlights
  • Dual Saju and Western birth chart analysis
  • AI-driven interpretation of astrological data
  • Detailed raw chart exploration
  • MBTI type comparison
  • Relationship compatibility readings
  • Multiple house division methods
Features
Read full description

Sidera computes the sky and the four pillars of the moment you were born, and talks with you about what is actually there. ■ Two systems, side by side Saju is the Korean reading of a birth moment: the year, month, day, and hour written as eight characters. The Western birth chart reads the same moment as planets, signs, and houses. Sidera runs both from the same birth data and sets them next to each other. You choose which to read from; the default is both. Where the two systems point at the same thing, and where they disagree, are called out separately. ■ The AI does not do the math Planetary positions and Saju pillars come from a deterministic engine. The AI reads what was computed and interprets it. The same birth details always produce the same chart. ■ Nothing is hidden behind the answer You can open the raw Saju chart and the raw birth chart in the app. Heavenly stems and earthly branches, the balance of the five elements, planetary positions, house cusps, aspects — all of it. Tap the small number in an answer and you go straight to the placement that sentence rests on. ■ Held up against MBTI Enter the MBTI type you know yourself by, and Sidera sets it beside the disposition read from your chart and names the axes that disagree. It does not rule one of them correct. The gap itself is what gets discussed. ■ You pick the method There is more than one way to divide the twelve houses. Whole Sign, Placidus, Equal, and Porphyry are all here, each with an explanation of what it does. On the Saju side you can decide whether to use true solar time and whether hours after 11pm belong to the next day. ■ Compatibility Register two people and Sidera lays the two skies and the two charts over each other, reading where they lock together and where they pull apart. Signing up gives you five free questions. Viewing the raw charts and managing profiles stays free. Sidera's readings are for reference. They do not replace medical, legal, or financial advice, or a conversation with a professional.

Screenshots

Pillowbook4 screens
Sidera4 screens

Verdict

The call

The clearest difference is in-app purchases: Pillowbook at none against Sidera's 3. Pillowbook also leads on ads (none vs shown). Sidera's advantage is update cadence (every 2 days vs every 2 months). On price, device support and iOS requirement 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. Sidera sells 3 one-off in-app purchases. Pillowbook asks for nothing beyond the download.

UpkeepUpdate frequency

Pillowbook ships an update every 2 months, Sidera every 2 days. The most recent releases landed on November 5, 2026 and October 31, 2026 respectively.

Scorecard4 real differences · 6 level
Pillowbook versus Sidera: the parameters behind the verdict, then further details
ParameterPillowbookSidera
PriceFreeFree
Rating5.0 (2 ratings) — better—
Positive reviews—100.0% of reviews
Number of ratings2 — better—
Update frequencyEvery 2 monthsEvery 2 days — better
AdsNo — betterYes
In-app purchasesNo — betterYes
MonetizationFree — betterFree with in-app purchases
DevicesiPhone, iPadiPhone, iPod
Requires iOS16.415.1 — better
Further details — not scored
Size36 MB36 MB
Age rating4+4+
DeveloperAndyTech, IncSu Jin Yang

Customer experience

Pillowbook

All ratings2 ratings
Positive100.0%
Neutral0.0%
Negative0.0%

Sidera

Written reviews1 reviews
Positive100.0%
Neutral0.0%
Negative0.0%

In-app purchases

None

Pillowbook

No in-app purchases

3 purchases

Sidera

One-time3
  • Light — 20 questions$2.99
  • Standard — 60 questions$6.99
  • Ultra — 150 questions$14.99

Questions

Is Pillowbook free?
Pillowbook is free to download, with no in-app purchases.
Is Sidera free?
Sidera is free to download, with in-app purchases available.
Do Pillowbook or Sidera have ads?
Sidera shows ads; Pillowbook does not.
Which is updated more often, Pillowbook or Sidera?
Pillowbook ships an update every 2 months, and Sidera every 2 days. Most recently, Pillowbook was updated on November 5, 2026 and Sidera on October 31, 2026.

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