Sr. Software Engineer - iOS

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!

We are seeking a highly skilled and experienced Sr. iOS Engineer to help shape the future of the T-Mobile T-Life App. In this role, you’ll collaborate with a talented team of mobile engineers to design, implement, and maintain high-quality iOS features that meet both business goals and user needs. You’ll be responsible for delivering scalable, performant, and secure mobile solutions that drive an exceptional customer experience across T-Mobile’s mobile ecosystem.
The ideal candidate brings deep expertise in modern iOS development practices—including architecture design, testing strategies, and performance optimization—along with strong collaboration and mentorship skills. You’ll contribute to technical direction, ship features to production, guide best practices, and grow within a culture that values innovation, ownership, and continuous learning.

*** This position will sit in Bellevue, WA; Overland Park, KS;  Frisco, TX, or Herndon, VA. This is not a remote role - this is a hybrid environment requiring 3 days a week in office.

Technical Execution

• Design, build, and maintain iOS features using Swift and the latest frameworks and tools.
• Deliver high-performance, secure, and user-friendly features that meet platform and business requirements.
• Write unit and integration tests to ensure quality and reliability across the app.
• Debug and profile performance bottlenecks across devices and OS versions.

Innovation & Product Impact

• Collaborate with Product and Design teams to explore innovative features and user flows.
• Prototype and implement solutions that solve complex problems or introduce new capabilities.
• Contribute to feature planning and development cycles that align with strategic product objectives.

Engineering Excellence & Leadership

• Help define and enforce architectural patterns (MVVM, Coordinator, etc.) for codebase scalability.
• Guide junior developers through code reviews, pair programming, and design discussions.
• Promote clean code, modular design, and reusable components across the platform.
• Lead or participate in engineering workshops, tech talks, and continuous improvement initiatives.

Tooling & Process

• Work within an Agile environment using GitLab for CI/CD, source control, and merge request workflows.
• Collaborate cross-functionally with QA, backend teams, and platform engineers.
• Identify and address system-level risks or architectural gaps early in the dev lifecycle.

Documentation & Communication

• Create and maintain clear technical documentation for features, APIs, and workflows.
• Communicate engineering decisions and trade-offs with stakeholders and team leads.

Education and Work Experience:

Education

• Bachelor’s Degree in Computer Science, Engineering, or related field (required)

Skills & Experience

Core iOS Development

• 4-7 years' experience developing iOS apps using Swift (Objective-C and C++ a plus)
• Expertise with Xcode, SwiftUI, UIKit, Interface Builder, and Apple SDKs
• Experience with Core Data, RESTful APIs, and networking frameworks
• Strong grasp of iOS memory management, concurrency (GCD), and threading

Architecture & Patterns

• Working knowledge of architectural patterns like MVVM, MVC, and Coordinator
• Solid understanding of common iOS design patterns: Singleton, Delegate, Observer

CI/CD & Version Control

• Proficient with GitLab, Git workflows, and continuous integration practices

Testing & Quality

• Experience building maintainable, testable codebases
• Skilled in writing unit tests and performing integration testing

Product Mindset

• Familiarity with Apple Human Interface Guidelines
• Ability to work closely with designers and product managers to ensure feature success

Security

• Understanding of iOS security best practices, including secure storage, communication (HTTPS), and OAuth

Soft Skills

• Strong problem-solving and debugging skills
• Clear communication and ability to work collaboratively across teams
• A commitment to continuous learning and growth in mobile development

Bonus Experience

• Familiarity with accessibility best practices (WCAG, VoiceOver testing)
• Experience integrating with backend services, feature flag systems, or A/B testing platforms
• Contributions to internal tooling, SDKs, or design systems

Knowledge, Skills and Abilities:

• Communication (Required)
• Customer Service (Required)
• Analytics (Required)
• Technical Writing (Required)

We pride ourselves on encouraging a culture of innovation, advocating for agile methodologies, and promoting transparency in all that we do. Join us in embodying the spirit of the 'Un-carrier' and make a tangible impact!

Our team is dynamic where no day is the same, and we are a diverse and inclusive team passionate about growth and innovation! If you're up to the challenge, apply today!

• At least 18 years of age
• Legally authorized to work in the United States

Travel:
Travel Required (Yes/No): Yes

DOT Regulated:
DOT Regulated Position (Yes/No): No
Safety Sensitive Position (Yes/No): No

Base Pay Range: $113,600 - $205,000

Corporate Bonus Target: 15%

The pay range above is the general base pay range for a successful candidate in the role. The successful candidate’s actual pay will be based on various factors, such as work location, qualifications, and experience, so the actual starting pay will vary within this range.

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. To find the pay range for this role based on hiring location, click here.

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, 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.