An online store can use the following security measures to protect its customers: 
1. Encryption of customer data - using encryption algorithms, sensitive customer data can be safeguarded from data breaches or cyber-attacks. 
2. Secure Payment Systems - using payment methods such as PayPal or Apple Pay, stores can ensure customers' payment information is securely processed. 
3. Two-Factor Authentication - adding a second layer of authentication can help protect customers' accounts from unauthorized access.
Identify three security measures an online store can use to protect its customers.