Last updated: July 8, 2026
These terms govern your use of Basis21 ("the app"), a blackjack basic-strategy trainer. By downloading or using the app, you agree to these terms. If you don't agree, don't use the app.
Basis21 does not involve real-money wagering, betting, or gambling of any kind, and is not affiliated with, endorsed by, or connected to any casino, card game, or gambling operator. It is provided for education and entertainment only.
The app's strategy recommendations and EV (expected value) figures are theoretical, based on the rule profile you select and standard play assumptions. Actual outcomes at any real table depend on the specific rules in effect, deck composition, and chance. Following correct basic strategy narrows the house edge — it does not guarantee winning, and does not eliminate the risk of financial loss if you choose to gamble with real money elsewhere. Basis21 is a training tool, not financial or gambling advice.
Subject to these terms, you're granted a personal, non-exclusive, non-transferable license to use Basis21 on devices you own or control, for your own non-commercial use. You may not reverse-engineer, redistribute, or resell the app or its content.
Basis21 offers an optional one-time, non-consumable in-app purchase ("Premium Unlock") that removes the free-tier practice limits. Purchases are processed by Apple (or Google, on Android) and are subject to their respective terms and refund policies — Basis21 does not process payments or hold your payment information directly. Except where required by applicable law, purchases are final and non-refundable through Basis21 directly; refund requests should go through the App Store or Play Store.
Basis21 stores your settings, drill history, and statistics locally on your device only. See the Privacy Policy for details. You're responsible for your device and any data stored on it.
Basis21 is provided "as is," without warranties of any kind, express or implied, including but not limited to accuracy, fitness for a particular purpose, or uninterrupted availability. While the strategy engine is built to established basic-strategy references, no guarantee is made that it is error-free.
To the maximum extent permitted by law, the developer is not liable for any indirect, incidental, or consequential damages arising from your use of the app, including any financial losses incurred while gambling with real money, whether or not informed by strategies practiced in this app.
The app and these terms may be updated from time to time. Continued use after an update means you accept the revised terms. The "Last updated" date above reflects the most recent change.
You may stop using the app at any time by uninstalling it. These terms remain in effect for as long as you use the app.
These terms are governed by the laws of Singapore, without regard to conflict-of-law principles.
Questions about these terms can be sent to vincentwahkit@gmail.com.