Once Upon a Galaxy vs Cost Exchange
Price, ratings, monetisation and update history for both games, side by side — with what reviewers say about each.
Once Upon a Galaxy
Embark on a fantasy card battling adventure where you draft unique captains and their friends to complete quests. Choose your path with diverse characters and strategic gameplay. Experience a game free of ads and AI art, focusing on player choice and engaging battles.
- Fantasy card battling
- Captain drafting
- Quest completion
- Strategic gameplay
- No AI artwork
- Asynchronous play
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Galaxy is FREE to play, has NO ADS, uses NO AI artwork. Will you choose Dorothy as your captain and help her and friends on their journey to complete their quests? Or Dragonmother and discover what will hatch from her dragon egg? Or maybe Indiana Clones, who will "clone" your best three treasures? It's all up to you!
Cost Exchange
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You are the duty officer on an air-defence console. Contacts appear on the scope. You do not know what they are. Query IFF, wait three seconds, then read the returned data — speed, altitude, radar cross section — and INFER the threat yourself. The game never labels it for you. Then the real decision: which weapon? An IR missile costs $150k. A radar missile costs $350k. CIWS costs $5k. The laser is free but needs time you may not have. Fire the expensive one at a cheap drone and you win the engagement while losing the operation. A leaker that reaches the centre damages a facility. Lose enough facilities and the operation is over — no matter how much money is left in the vault. • Infer, don't be told — no automatic threat labels, ever • Four weapons with real trade-offs in range, cost and reload • Ammunition economy: every shot is a decision you pay for • Graded S to F on five criteria, with hard caps for downing a friendly • DAILY OPERATION — the same operation for everyone, one attempt a day • FREE OPERATIONS — endless seeded operations across four difficulty tiers No ads. No energy timers. No in-app purchases. Everything is unlocked. iPhone and iPad.
Screenshots
Verdict
The clearest difference is in-app purchases: Cost Exchange at none against Once Upon a Galaxy's 50. Once Upon a Galaxy's advantage is iOS requirement (15.0 vs 17.0). On price, ads 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
Both are free to download. Once Upon a Galaxy sells 44 one-off in-app purchases. Cost Exchange asks for nothing beyond the download.
| Parameter | Once Upon a Galaxy | Cost Exchange |
|---|---|---|
| Price | Free | Free |
| Rating | 4.8 (1.4K ratings) — better | — |
| Positive reviews | 83.4% of reviews | — |
| Number of ratings | 1.4K — better | — |
| Update frequency | Fortnightly | — |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free with in-app purchases | — |
| Devices | iPhone, iPad, iPod — better | iPhone, iPad |
| Requires iOS | 15.0 — better | 17.0 |
| Further details — not scored | ||
| Size | 195 MB | 3 MB |
| Age rating | 9+ | 4+ |
| Developer | Million Dreams Games | Burhanettin Uludag |
Bugs and requests
Once Upon a Galaxy
Reported bugs
3 issues- Black screen on startup
- Infinite loading issues
- Progression loss after updates
Requested features
5 requests- More hero/card variety
- Improved tutorial and learning tools
- Offline/save progress mode
- Cosmetic/non-gameplay monetization
- Competitive/ranked modes
Cost Exchange
Not enough reviews yet to summarise bugs or requests.
In-app purchases
Once Upon a Galaxy
- 600 Gems (September deal)$4.99
- 600 Gems (July deal)$4.99
- Welcome Bundle3 variants$4.99
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- 500 Gems2 variants$4.99
- October 2026 Galaxy Pass$9.99
- September 2026 Galaxy Pass$9.99
- 1300 Gems (August deal)$9.99
- August 2026 Galaxy Pass$9.99
- July 2026 Galaxy Pass$9.99
- June 2026 Galaxy Pass$9.99
- March 2026 Galaxy Pass$9.99
- May 2026 Galaxy Pass$9.99
- April 2026 Galaxy Pass$9.99
- February 2026 Galaxy Pass$9.99
- December Galaxy Pass$9.99
- January 2026 Galaxy Pass$9.99
- November 2025 Galaxy Pass$9.99
- October 2025 Galaxy Pass$9.99
- September 2025 Galaxy Pass$9.99
- July 2025 Galaxy Pass$9.99
- August 2025 Galaxy Pass$9.99
- June 2025 Galaxy Pass$9.99
- May 2025 Galaxy Pass$9.99
- 1,100 Gems2 variants$9.99
- April 2025 Galaxy Pass$9.99
- March 2025 Galaxy Pass$9.99
- February 2025 Galaxy Pass$9.99
- Galaxy Pass$9.99
- Swishbuckler Chromaria Bundle$14.99
- Chromarian Chromaria Bundle$14.99
- Remi Chromaria Bundle$14.99
- Galaxy Reroll$14.99
- Candylar Reroll$14.99
- Mythbound Reroll$14.99
- Thanatos Mythbound Bundle$14.99
- Baldr Mythbound Bundle$14.99
- Hecate Mythbound Bundle$14.99
- Candylar Goat T Preorder$14.99
- Candylar Beanstalk Preorder$14.99
- Candylar Candy Pandy Preorder$14.99
- 2,300 Gems2 variants$19.99
- Winter Bundle$29.99
- 6,000 Gems$49.99
- 14,000 Gems2 variants$99.99
Cost Exchange
No in-app purchases
Questions
Is Once Upon a Galaxy free?
Is Cost Exchange free?
Do Once Upon a Galaxy or Cost Exchange have ads?
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