Want same-day delivery on an eBay (NASDAQ:EBAY) purchase? It's now possible for San Franciscans placing $25+ orders with certain local stores, courtesy of the eBay Now iOS app. Presumably, more cities and platforms will be added in time. eBay's move is aimed not only at Amazon (NASDAQ:AMZN), which has said same-day isn't economical "on a broad scale," but at Groupon (NASDAQ:GRPN), which wants to evolve into a soup-to-nuts local commerce partner. Shopkick may also be a target. A $5/item delivery fee applies to each purchase.