To combat phone theft, several lawmakers over the last year have put pressure on manufacturers and wireless carriers to include smarter antitheft technology on smartphones. A group of tech and phone companies on Tuesday said they were on board with the idea. CTIA, the industry trade group that represents the carriers, said over a dozen companies, including Apple, AT&T, Google, Samsung Electronics and Verizon Wireless, had committed to offering free antitheft software for cellphones at the beginning of next year.