Reviewing the financial reports of many mobile operators shows a similar story in how their costs breakdown.  There's roughly an 80:20 split between operational (80%) and capital (20%) expenditure.  Capital expenditures cover the amortized investment in the licenses and building the network infrastructure.  The bulk of a mobile operator's costs are operational expenditures, hence the importance of EBITDA (Earnings before Interest, Tax, Depreciation and Amortization) as a metric of an operator's financial performance; generally in the 25-35% range.

The operational expenditures breakdown into roughly:

• 40% Marketing and sales, building the brand, paying for all those TV adverts, sponsorship, subsidies on phones, etc;
• 25% Interconnect, cost of calls terminated on other operators, generally a regulated cost structure;
• 20% Technical operations; and
  
• 15% Other costs covering customer care, offices, etc.

Diving into Technical Operations in a little more detail, it roughly breaks down three ways between:

• 7% Transport, most mobile operators have to rent E1s or T1s from incumbent carriers.  As mobile broadband grows, operators need to find ways to have this cost grow in line with revenue not data volume;
• 7% People, hot topic and the focus of outsourced network operations a roughly $10B business, which is about breaking down organizational silos to enable better teamwork, removal of redundancy and leveraging economies of scale; and
• 6% Other (maintenance and site leasing), here we see suppliers being squeezed on maintenance contracts and options such as site sharing.

Other hot topics such as LTE (Long Term Evolution) and Flat IP are really about managing the longer term capital investment as data traffic grows.  But the part of the financial analysis I've not mentioned yet is the revenues.  A tougher nut to crack than managing costs, but nonetheless the biggest number in the financial reports, and one that is most open to competition.  Hence, just using the raw numbers in an operator's financials to weight the priorities; revenue maintenance / growth should be as important as all the cost saving measures combined.