Short answer: It depends on what you mean by “fastest.”

• If you want a fashion-focused shopping app with built-in express/next‑day options, Zalora is the top choice — it’s the Philippines’ dedicated fashion marketplace and offers express delivery options for clothing and accessories. (Parcels.app)

• If you want the highest chance of same‑day delivery (especially inside Metro Manila), Lazada and Shopee both offer express/same‑day or next‑day options for some sellers/items — but speed varies a lot by seller and courier. Lazada advertises a same‑day/express service for Metro Manila orders placed before cutoffs. (noypigeeks.com)

• If “fastest” means literally fastest (minutes to a few hours) and you’re willing to arrange pickup rather than rely on a marketplace’s logistics, on‑demand couriers like Lalamove, GrabExpress (and similar last‑mile providers such as Paxel, Transportify/XpressRun) can deliver fashion items the quickest because you can request immediate pickup from a store or seller. These services are the usual choice for guaranteed same‑day, on‑demand deliveries in Metro areas. (Lalamove.com)

Recommendation (practical):

• If you want a fast, reliable fashion purchase with the least hassle: try Zalora (select express/next‑day shipping). (Parcels.app)
• If you need it the same day right now: buy from a local seller on Lazada/Shopee that offers same‑day and/or ask the seller to dispatch with Lalamove/GrabExpress for on‑demand pickup. (noypigeeks.com)

If you tell me your city (e.g., Metro Manila, Cebu, Davao) I can say which of these options realistically gives you same‑day delivery where you are and point to where to select the express option.