If you care about privacy and you are looking for a loyalty card manager, Catima and CardWarden are two of the most privacy-respecting options you will find. They take fundamentally different approaches to the same goal - keeping your card data safe - and the right choice depends on what trade-offs you are willing to make.
This is an honest comparison from the person who built CardWarden. Catima is a genuinely great project, and I have a lot of respect for what the open-source community has built. I will be upfront about where Catima shines and where CardWarden has the edge.
Catima is a free, open-source loyalty card app for Android that takes the "air-gapped" approach to privacy - no internet permission, no cloud, no accounts. CardWarden is an encrypted card manager for Android and iOS that takes the "encrypted cloud" approach - your data syncs across devices, but it is encrypted on your device before it ever reaches a server, and only you hold the key. If you want a zero-cost, fully offline card wallet on Android, Catima is excellent. If you want encrypted sync, family sharing, and cross-platform support, CardWarden was designed for that.
Two Privacy-First Approaches
Catima is a free, open-source (GPLv3) loyalty card and ticket manager for Android. It is available on Google Play and F-Droid, and its source code is fully auditable on GitHub. The app does not even request internet permission - your card data physically cannot leave your device through the app. No accounts, no sign-ups, no tracking. It is the digital equivalent of an air-gapped computer.
CardWarden takes a different approach. I built it to solve a problem Catima cannot - syncing cards across multiple devices and sharing them with family members - without giving up privacy. CardWarden uses zero-knowledge encryption (ChaCha20-Poly1305, PBKDF2, ECDH) so your data is encrypted on your device before it touches any server. I, as the developer, cannot read your data even if I wanted to. The server facilitates sync and sharing but never has access to the plaintext.
Both approaches are legitimate answers to the privacy question. Catima says "just never connect to the internet." CardWarden says "connect, but encrypt everything so thoroughly that the connection is meaningless to anyone without your key." The right answer depends on whether you need cloud sync and family sharing or whether you are happy with a single-device, single-user setup.
Feature Comparison
| Feature | CardWarden | Catima |
|---|---|---|
| Loyalty card storage | Yes | Yes |
| Gift card management | Yes, with balance checking | Storage only, no balance check |
| Platform support | Android & iOS | Android only |
| Cloud sync | Yes (zero-knowledge encrypted) | No |
| Family sharing | Yes, with role-based access | No |
| Kids Mode | Yes, no account needed | No |
| End-to-end encryption | Yes (ChaCha20-Poly1305) | No (local storage only) |
| Open source | No (white paper published) | Yes (GPLv3) |
| Works offline | Yes, always | Yes, always |
| Home screen widgets | Yes | No |
| Data export | Yes (spreadsheet or encrypted) | Yes (file export) |
| Import from other apps | Yes (screenshots) | Yes (Stocard, FidMe, Voucher Vault) |
| Biometric lock | Yes | No |
| No ad tracking | Yes | Yes |
| Price | Paid plans | Yes, completely free |
Where CardWarden Pulls Ahead
Cross-platform support
This is the most straightforward difference. Catima is Android-only with no iOS version and no plans to build one. If you or anyone in your household uses an iPhone, Catima is not an option for them.
CardWarden runs on both Android and iOS. Your cards sync between devices regardless of which platform you use. Switch phones, switch ecosystems - your cards follow you.
Cloud sync with zero-knowledge encryption
Catima stores everything locally. If you lose your phone, your cards are gone unless you manually created a backup file and stored it somewhere. There is no automatic sync between devices - if you carry a phone and a tablet, you are managing two separate card collections.
CardWarden syncs your cards across all your devices automatically, and the sync is zero-knowledge encrypted. Your data is encrypted on your device using ChaCha20-Poly1305 before it is transmitted. The encryption key is derived from your master password using PBKDF2 with 600,000 iterations. The server stores encrypted blobs it cannot decrypt. You get the convenience of cloud sync without trusting anyone with your data.
Family sharing
This is the feature that drove me to build CardWarden in the first place. My wife and I share grocery gift cards, and managing them without sync was a constant source of friction - duplicate scans, stale balances, no way to know what the other person had already spent.
CardWarden lets you create shared "pockets" (folders of cards) and invite family members with role-based access:
- Viewer - can see cards but not modify anything
- User - can use cards at checkout and update balances
- Editor - full access to add, edit, and remove cards
The sharing is end-to-end encrypted using ECDH key exchange. There is also a Kids Mode that lets children join without creating an account or providing personal data.
Catima has no sharing features. If two family members both need a card, each person adds it independently and manually tracks any changes.
Gift card balance checking
CardWarden has a built-in browser that opens the retailer's balance-check page, pre-fills your card number and PIN, and updates the stored balance after verification. When a family member uses a shared gift card, the new balance syncs to everyone's device in real time.
Catima stores gift cards but does not offer balance checking. You have to manually visit each retailer's website and update balances yourself.
Encryption at rest
Catima stores card data in plain text on the local filesystem. If someone gets physical access to your unlocked phone or extracts data from a backup, your card numbers and details are readable. The app has no built-in biometric lock or PIN protection.
CardWarden encrypts all card data at rest, whether stored locally or synced to the cloud. Even on your own device, the data is encrypted and protected behind biometric authentication or your master password.
Where Catima Wins
Catima has real strengths, and I want to be honest about them.
Catima's advantages
- Completely free - No paid tiers, no subscriptions, no in-app purchases. Everything Catima does is free, forever.
- Open source (GPLv3) - The entire codebase is on GitHub. Anyone can audit the code, verify the privacy claims, and contribute improvements. That is a level of transparency closed-source apps cannot match.
- No internet permission - The app does not even request network access. This is the strongest possible privacy guarantee - your data physically cannot be transmitted. No trust required.
- Available on F-Droid - For users who avoid the Google Play Store, Catima is available through F-Droid, the open-source app repository.
- Import from multiple apps - Catima can import cards from Stocard, FidMe, Loyalty Card Keychain, and Voucher Vault. Great for migrating from a shuttered app.
- Smartwatch support - Catima integrates with Gadgetbridge for displaying barcodes on compatible smartwatches.
What CardWarden does not do
- Not open source (security white paper is public)
- Not available on F-Droid
- Has paid tiers for cloud and family features
- Indie app from a solo developer (smaller community)
- No Gadgetbridge integration
If you want a free, fully open-source card wallet that is completely air-gapped from the internet, Catima is genuinely hard to beat. It does one thing and it does it well. CardWarden is not trying to replace Catima for that use case - it is built for people who need more (sync, sharing, encryption, cross-platform) and are willing to pay for the infrastructure that makes those features possible.
Privacy comparison
This is an unusual comparison page because both apps are strong on privacy. The difference is philosophical, not a question of one being better than the other.
Catima collects nothing. Zero. The app has no internet permission, so it cannot send data even if it wanted to. This is the gold standard for privacy purists.
CardWarden collects your email address for account creation and anonymous analytics (OS version, device model, app version - no advertising IDs). All card data is encrypted with a key only you hold. The server stores encrypted blobs it cannot decrypt. In practice, the privacy difference between "no data leaves your device" and "data leaves your device but is mathematically unreadable" is small - but the first one is simpler to verify.
Pricing
Catima is free. No paid tiers, no premium features, no subscriptions. The project is community-maintained and funded by voluntary contributions.
CardWarden offers a free tier and three paid tiers:
The free tier exists so you can get a feel for the app - explore the interface, add a few cards, and see if it fits. It has a card limit and is not designed for day-to-day use. If you want to try the full experience, the yearly Cloud and Family plans include a free trial, which is a better way to see everything CardWarden can do before committing.
- Premium Offline - A one-time, lifetime purchase. Full offline card management, encryption, biometric lock. No cloud, no subscription.
- Premium Cloud - Monthly or yearly subscription for individuals. Adds cloud backup, multi-device sync, and related features. Free trial available on the yearly plan.
- Premium Family - Monthly or yearly subscription covering five Premium Cloud seats, shared pockets, role-based access, push notifications, and Kids Mode. Free trial available on the yearly plan.
Cloud features cost money to operate (encrypted sync infrastructure is not free), so those tiers are subscriptions. The offline tier is one-time because it does not generate ongoing server costs. CardWarden does not monetize your data, show ads, or earn merchant commissions - subscriptions and one-time purchases are the entire business model.
Frequently Asked Questions
Is Catima available on iOS?
No. Catima is Android-only, and there are no plans for an iOS version. If you need a loyalty card app that works on both Android and iOS, CardWarden supports both platforms with encrypted cloud sync between them.
Does Catima have cloud sync?
No. Catima stores all data locally on your device with no cloud sync. You can manually export your cards to a file and back them up to a cloud storage service yourself, but the app does not offer automatic multi-device sync. CardWarden offers encrypted cloud sync that keeps your cards updated across all your devices automatically.
Is CardWarden open source?
CardWarden is not open source. However, the security architecture is fully documented in a public white paper, including the encryption algorithms and how zero-knowledge sync works. Catima's code is auditable by anyone, while CardWarden's security model is verifiable through its documentation and the fact that the server literally cannot decrypt your data.
Which app is more private - Catima or CardWarden?
Both apps take privacy seriously, but they use fundamentally different approaches. Catima has no internet permission at all - your data physically cannot leave your device through the app. CardWarden uses zero-knowledge encryption - your data syncs to the cloud, but it is encrypted on your device before transmission and cannot be read by the server. Catima's approach is simpler and more verifiable. CardWarden's approach gives you cloud sync and family sharing without sacrificing privacy. It depends on whether you value air-gapped isolation or encrypted convenience.
Is CardWarden free?
CardWarden has a free tier, but it has a card limit and is really there so you can try the app and get a feel for how it works. For day-to-day use, the paid tiers are a better fit. If you want to try the full experience risk-free, the yearly Cloud and Family plans include a free trial. Premium Offline is a one-time lifetime purchase for full offline features, while Premium Cloud and Premium Family are subscriptions that cover the ongoing cost of encrypted cloud sync and family sharing infrastructure.
The Bottom Line
Catima and CardWarden are both privacy-respecting card managers. They just solve the problem differently.
Choose Catima if you want a completely free, open-source card wallet that is fully air-gapped from the internet. You use Android, you only need one device, and you are comfortable managing your own backups. You value code transparency and the ability to verify every line of source code yourself.
Choose CardWarden if you want encrypted cloud sync, family sharing, and cross-platform support. You need your cards on multiple devices or want to share cards with household members. You value zero-knowledge encryption that gives you cloud convenience without trusting anyone with your data.
Both are good choices. They just answer different versions of the same question.
CardWarden is opening for beta testing soon. If you want to try an encrypted card manager that syncs across your household, sign up for early access.