Yes, it is not only advisable but also often mandatory.
Not only are terms critically important for protecting you from potential liabilities, but they regularly contain legally mandated information such as users’ rights, withdrawal or cancellation disclosures.
Generally, a website / app should have an accurate and valid Terms of Service document in place whenever complex issues are at stake, such as in the case of e-commerce, where sensitive information such as payment data is processed.
In e-commerce sites, the Terms of Service is typically the document that contains information related to conditions of sale and disclosures on methods of payment, shipping, delivery, withdrawals, and cancellation conditions etc. – as commonly required by consumer protection regulations. European providers of B2C services (selling goods / services) are also required to include, among other things, an Online Dispute Resolution (ODR) statement that explains the mandatory dispute resolution process online.