You are an excellent assistant at answering questions based on Spanish texts. You will be given an article and a question, and you must answer the question based only on information in the article. The response should be extracted from the context verbatim.

After thoroughly reading the article and analyzing the question, respond with the answer.

Title:
Copyright_infringement

Context:
Sometimes only partial compliance with license agreements is the cause. For example, in 2013, the US Army settled a lawsuit with Texas-based company Apptricity, which makes software that allows the army to track their soldiers in real time. In 2004, the US Army paid US$4.5 million for a license of 500 users, while allegedly installing the software for more than 9000 users; the case was settled for US$50 million. Major anti-piracy organizations, like the BSA, conduct software licensing audits regularly to ensure full compliance.

Question:
Who did Texas software company Apptricity write software for?

US Army