At T-Mobile, we invest in YOU! Our Total Rewards Package ensures that employees get the same big love we give our customers. All team members receive a competitive base salary and compensation package - this is Total Rewards. Employees enjoy multiple wealth-building opportunities through our annual stock grant, employee stock purchase plan, 401(k), and access to free, year-round money coaches. That’s how we’re UNSTOPPABLE for our employees!T-Mobile is America’s supercharged Un-carrier, delivering an advanced 4G LTE and transformative nationwide 5G network that will offer reliable connectivity for all. Principal Engineers, Software located in Bellevue, WA will understand system protocols, how systems operate and data flows.Independently develop a full mobile app software stack with test automation.Conduct independent research into new technologies and software stacks.Drive engineering projects by developing software solutions, conducting tests and inspections, prepare reports and calculations.Contribute to designs to implement new ideas which improve an existing and new system, process and service.Review existing designs and processes to highlight more efficient ways to complete existing workload more effectively through industry perspectives.Write basic documentation on how technology works.Document systems designs, presentations, and business requirements for consumption and consideration at the manager level.Collaborate with technical teams and utilize system expertise to deliver technical solutions.Contribute to the development of others through mentoring or in house workshops and learning sessions, growing mid-level and associate engineers.Contribute to new and existing technology options that support business goals.Telecommuting is permitted, but applicant must work from the worksite location at least 3-4 days per week.No additional national or international travel is anticipated.Skill requirements: (1) Working in Android App Development projects with a strong focus on architecture and design;(2) Using Kotlin, Jetpack libraries, and Compose for building modern, efficient, and scalable Android applications;(3) Working with IoT protocols, SignalR technologies, and integrating IoT devices with mobile applications;(4) Leading a development team, providing technical guidance, and ensuring adherence to best practices in Android development and IoT integration;(5) Leading Android development, overseeing and guiding iOS development efforts, ensuring seamless integration and consistent user experiences across platforms; and(6) Understanding of mobile app security best practices, including data encryption, secure communication protocols, and threat mitigation strategies to protect user data and ensure app integrity.Experience and education requirements:PRIMARY REQUIREMENTS: Master's Degree in Computer Science, Software Development, Information Systems or its foreign equivalent, and 5 years of relevant work experience.ALTERNATIVE REQUIREMENTS: Bachelor's Degree in Computer Science, Software Development, Information Systems or its foreign equivalent, and 7 years of relevant work experience.Experience and education requirements:PRIMARY REQUIREMENTS: Master's Degree in Computer Science, Software Development, Information Systems or its foreign equivalent, and 5 years of relevant work experience.ALTERNATIVE REQUIREMENTS: Bachelor's Degree in Computer Science, Software Development, Information Systems or its foreign equivalent, and 7 years of relevant work experience.Additional: Location: Bellevue, WAThis position is eligible for the employee referral program.How to apply:Visit https://careers.t-mobile.com/Create a candidate profile, and apply to REQ362183.OTHER: Work hours: 40 hours/week. Washington Pay Range: $212,202.00 to $234,700.00/year.At least 18 years of ageLegally authorized to work in the United StatesTravel:Travel Required (Yes/No): NoDOT Regulated:DOT Regulated Position (Yes/No): NoSafety Sensitive Position (Yes/No): No Candidate’s pay will be based on various factors, such as work location, qualifications, and experience. At T-Mobile, employees in regular, non-temporary roles are eligible for an annual bonus or periodic sales incentive or bonus, based on their role. Most Corporate employees are eligible for a year-end bonus based on company and/or individual performance and which is set at a percentage of the employee’s eligible earnings in the prior year. Certain positions in Customer Care are eligible for monthly bonuses based on individual and/or team performance. At T-Mobile, our benefits exemplify the spirit of One Team, Together! A big part of how we care for one another is working to ensure our benefits evolve to meet the needs of our team members. Full and part-time employees have access to the same benefits when eligible. We cover all of the bases, offering medical, dental and vision insurance, a flexible spending account, 401(k), employee stock grants, employee stock purchase plan, paid time off and up to 12 paid holidays - which total about 4 weeks for new full-time employees and about 2.5 weeks for new part-time employees annually - paid parental and family leave, family building benefits, back-up care, enhanced family support, childcare subsidy, tuition assistance, college coaching, short- and long-term disability, voluntary AD&D coverage, voluntary accident coverage, voluntary life insurance, voluntary disability insurance, and voluntary long-term care insurance. We don't stop there - eligible employees can also receive mobile service & home internet discounts, pet insurance, and access to commuter and transit programs! To learn about T-Mobile’s amazing benefits, check out www.t-mobilebenefits.com.Never stop growing! As part of the T-Mobile team, you know the Un-carrier doesn’t have a corporate ladder–it’s more like a jungle gym of possibilities! We love helping our employees grow in their careers, because it’s that shared drive to aim high that drives our business and our culture forward. By applying for this career opportunity, you’re living our values while investing in your career growth–and we applaud it. You’re unstoppable! T-Mobile USA, Inc. is an Equal Opportunity Employer. All decisions concerning the employment relationship will be made without regard to age, race, ethnicity, color, religion, creed, sex, sexual orientation, gender identity or expression, genetic information, national origin, religious affiliation, marital status, citizenship status, veteran status, the presence of any physical or mental disability, or any other status or characteristic protected by federal, state, or local law. Discrimination, retaliation or harassment based upon any of these factors is wholly inconsistent with how we do business and will not be tolerated. Talent comes in all forms at the Un-carrier. If you are an individual with a disability and need reasonable accommodation at any point in the application or interview process, please let us know by emailing ApplicantAccommodation@t-mobile.com or calling 1-844-873-9500. Please note, this contact channel is not a means to apply for or inquire about a position and we are unable to respond to non-accommodation related requests.