Contact support
Email support@doublestick.ai for product, privacy, or accessibility help. Support is provided in English; Korean requests are also welcome.
Keep credentials private. Never email an authentication token, raw API account UUID, advertising ID, install ID, provider alias, one-time verification code, or payment information. Vokai support will not ask you to send a password or token.
Lessons, audio, and progress
A lesson will not load
Confirm that the device is online, close and reopen Vokai, and try again. A fallback lesson may appear if the API cannot return the normal word set.
Audio is silent
Check Vokai's sound setting and the device's media volume. Some words may use device text-to-speech, so installed language voices can affect playback.
Progress looks different
Some detailed mastery data stays local while validated sessions and totals are synced to Vokai's API. Include what changed and when, without including account identifiers.
A translation seems wrong
Send the source and target languages, the word, and the sentence shown. Do not include unrelated personal information in the report.
Ads, Offers, and points
An ad is unavailable
Ads remain off if Google UMP cannot confirm that ad requests are permitted, if the placement is not configured, or if no inventory is available. Rewarded ads are optional and may not be available every time.
An Offer did not credit
Tapjoy is contacted only when you explicitly open Offers. Wait for the advertiser's stated validation period, then use the support route provided inside the Tapjoy offerwall when available. Include the offer name and approximate completion time, but do not send Vokai or Tapjoy credentials.
Can coins be redeemed?
Eligible coins can be redeemed in the app for a third-party digital gift card once your redeemable balance reaches the minimum shown in the app (currently USD 3.00). Redemption requires a verified email address, is limited to users 18 or older, and requests are held for a review period (up to 7 days) before the card is emailed. Coins cannot be exchanged for cash, purchased, or transferred between users. If a redemption seems stuck beyond the review period, contact support with the request date — never send credentials or the full card code.
Notifications and Android widget
Vokai reminders and word-of-day notifications are scheduled locally after permission is granted. Change the reminder settings in Vokai or revoke notification permission in Android settings. Battery optimization or device scheduling rules can delay a local notification.
The word-of-day widget uses a small locally stored upcoming-word set and refreshes when the app opens or Android requests an update. If it is stale, open Vokai once and then add the widget again. Deleting Vokai data clears the widget's local data.
Privacy, analytics, and deletion
The optional Analytics switch in Profile controls both PostHog product analytics and Tenjin attribution. They begin only after opt-in and the choice can be revoked. Google UMP handles AdMob privacy choices only. A Tapjoy-enabled production version must present its own applicable offer privacy choice before connection and provide withdrawal or opt-out controls; without those controls, Offers remains unavailable in production.
Read the Privacy Policy for full provider and retention details. For deletion, the fastest route is Profile > Delete my data. If you cannot use the app, follow the support-assisted deletion process.
Details that help us investigate
A useful report includes:
- the Vokai app version and Android version code shown by the installed build;
- device model, Android version, and app language;
- the screen and action involved;
- what happened, what you expected, and the approximate local time; and
- a screenshot only after checking that it contains no identifiers, notifications, or other private information.
Operator: DoubleStick UG (haftungsbeschränkt)
Address: Urbanstr. 182, 10961 Berlin, Germany
Email: support@doublestick.ai
Phone: +49 176 55374207
Company details: Impressum