A small but influential group of mobile operators are introducing radical new approaches to network build-out, to disruptive effect, in some key world markets. Free Mobile’s skilful harnessing of its existing fiber and WiFi assets to reduce cellular costs and undercut its rivals’ pricing has shaken up the French market in recent years, and parent Iliad hopes to do the same in Italy now. A similar approach might be taken by Germany’s new mobile entrant, 1&1 Drillisch, if it buys 5G spectrum (see lead item). Reliance Jio has rewritten all the rules in India, and now ecommerce giant Rakuten plans to do the same in the entrenched market of Japan. Superficially, what the first three have in common is an…