Shein delivers, but operates under Chinese law, collects extensive personal data, and has serious unresolved labour practice concerns.
Shein is not a scam — orders arrive and the site is technically functional — but "it delivers" is a low bar. UK consumer protection law does not fully apply to purchases from Chinese-registered companies, meaning your rights on returns and faulty goods are weaker than with a UK retailer.
The app requests extensive device permissions and all data is governed by Chinese law, not UK GDPR. If you must buy, use the website over the app, pay by credit card for Section 75 protection, and factor in likely customs charges on orders over £135.