MISTR review for Shopify Marketplace Connect

May 18, 2026

We reinstalled this app in April 2026 having previously used it in 2019. Upon reinstallation the app merged our new eBay account with our defunct 2019 legacy account and published our entire product catalogue of 1,000+ products to eBay without our authorisation, including brands we are not licensed to sell on eBay, putting our seller account at risk of suspension. We had to manually emergency-end all listings ourselves. Three weeks later, after dealing with multiple support agents who repeatedly suggested the same failed fixes, the legacy account data is still present in their system. We have also discovered that a former employee who left our business in 2020 still has active credentials stored within the app, representing a serious data security risk. We have now been forced to file a formal complaint with the ICO regarding the unlawful retention of personal data. The app itself may work well for new users, but if you have any history with it under a previous account or trading name, be warned that your old data is never deleted and can cause serious problems when you return. We would not recommend this app to any business until their data retention and account management processes are significantly improved.