StampChip
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In private testing on Android

A casino diary that holds up at tax time

Log every session the way IRS Publication 529 describes, with time-and-place check-ins that can't be rewritten later. It all stays on your phone.

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Free to log. The tax-year export is a one-time purchase.

  • No account
  • Works with no signal
  • Encrypted backups
  • No tracking
StampChip showing a session in progress at Riverbend Casino with two check-ins, money in, and Cash out, Check in and Edit buttons

3 check-ins at Riverbend Casino

  1. 38 m from the venue

    #a3f9c21d

  2. 24 m from the venue

    #5e10b7a4

  3. Session started

    #0c2d98f1

Each stamp is written once and hashed with the one before it, so a session can't quietly move to another day or place.

Three taps per session

Start when you sit down, check in while you play, cash out when you leave. The diary writes itself, and at tax time it becomes the pack your preparer works from.

  1. The Start a session form with the date, time, Riverbend Casino, its address and the Slots game selected

    Start a session

    The date and time fill themselves. Pick the casino near you, the game and machine or table, and what you're putting in.

  2. A session opened in the list, showing its check-in stamps with time, distance from the venue and hash

    Check in while you play

    One tap records when, where and how far you are from the venue. It works with no signal.

  3. The Cash out form with money out, tax withheld and the W-2G fields

    Cash out

    Enter what you left with. Net result, tax withheld and W-2G details land on the session and your year totals update.

  4. At tax time, hand your preparer the pack

    The Preparer Pack turns the year into the diary Publication 529 describes, an annual summary with the Schedule A computation on both deduction bases, and a workbook with every session as a row your preparer can check. One purchase per tax year, made in the app and built on your phone from your own diary.

    See the full pages in the guidePricing

    The first page of the pack: the annual summary with winnings, losses, net result and W-2G totals, and the deduction computation on both the 100 percent and the 90 percent basisAnnual summary and Schedule A computation A page of the printed session diary: one row per session with date and time, type of wager, game and unit, establishment and address, who was present, money in, money out, net, W-2G and evidence codes, grouped by month with subtotalsSession diary, one row per session The Summary sheet of the preparer workbook with session counts, headline figures and the Forms W-2G totals, and the tabs for the Sessions, W-2G, Evidence, By type, By month, By casino-day, References and Notes sheetsPreparer workbook, nine sheets

    Sample pages with made-up sessions. Tap a page to see it full size.

Try the three taps in the demo

Every detail Publication 529 asks for

The IRS says a gambling diary should record at least four things. In StampChip each one is a field, not a free-text note.

Publication 529 asks forThe date and type of each wager or wagering activity
Date, start and end time, game, and machine or table number
Publication 529 asks forThe name and address or location of the gambling establishment
The venue's name and address, plus your location at each check-in
Publication 529 asks forThe names of other people with you
Who was with you, or that you were alone
Publication 529 asks forThe amounts you won or lost
Every buy-in, money out, net result, W-2G winnings and tax withheld

Keep the proof alongside it: W-2Gs, tickets, slips and bank records. Every entry is timestamped when saved, later edits stay in its history, and voided entries stay on record.

Your diary never leaves your phone

No account, no server, no analytics. Nothing you log is sent to BFVZ.

Stored on the device

Sessions live in your phone's own storage. The only outside call is to Google when you tap Use my location to find casinos near you.

Encrypted backups you keep

One encrypted file you put where you like: Drive, an email to yourself, or your computer.

Only you can open it

Your passphrase or recovery code opens a backup. BFVZ never sees either and can't reset them.

Because nobody else holds a key, losing both your passphrase and recovery code means losing that backup.

Read the privacy policy

The Settings screen with the Backup block: Back up now, Restore from a backup, Recovery code

Free to log. Pay once at tax time.

Everything you need to keep the diary is free. The Preparer Pack is optional, once per tax year.

Free

$0

The full diary, as long as you use it.

  • Unlimited sessions, check-ins and W-2Gs
  • Year and day views, by-place and by-day tables
  • Encrypted backup and restore
  • Works offline
Join the private test

For tax season

Preparer Pack

Price at launch

One-time per tax year, bought in the app through Google Play.

  • Printable diary in the order Publication 529 lists
  • Workbook for your preparer with every session
  • W-2G reconciliation and both deduction bases
See what's in the pack

Questions

Does it work on the casino floor with no signal?

Yes. The app, the built-in casino list and your diary are all stored on the phone. Check-ins use the phone's own location fix.

What happens if I lose my phone?

Restore from your backup on the new phone with your passphrase or recovery code. Without a backup the diary is gone with the phone; BFVZ has no copy to give you. The app reminds you when sessions aren't backed up yet.

Can BFVZ see my sessions?

No. There is no account and nothing is uploaded. Backups are encrypted on your phone before they leave it, and you choose where they go.

Is the check-in stamp proof?

It's evidence you generate yourself: a time, a place and a hash chain that shows the entry wasn't rewritten. It supports a diary; it doesn't replace casino win/loss statements, W-2Gs or bank records.

Does it replace a tax preparer or lawyer?

No. StampChip helps you keep records. What those records mean for your return, how to report, and what an examiner will accept are questions for a licensed professional. See the terms.

Is there an iPhone version?

Testers on iPhone use the same app from Safari, added to the home screen; it works the same way, with the same code. A store version for iPhone is planned after the Android launch.

Something else? hello@stampchip.com

Help test it before launch

If you play regularly and would use a diary like this, ask for an invite. Testers get the app before the store listing and a say in what ships.

Ask for an invite Try the demo first