Subho Halder, co-founder and CEO of Appknox, joins Vandana Verma to discuss building a mobile security company, how a founder’s role changes over time, and why customer focus, resilience, vision, and fast learning matter.
Subho’s security journey began roughly 13 years before the interview, when smartphones and mobile applications were still becoming mainstream. Curiosity about how iPhones and Android devices worked led him to experiment with mobile security, initially through playful attempts to access friends’ devices.
He wrote a paper about Android malware and was invited to present it at ClubHack, where he encountered India’s wider cybersecurity community for the first time. More research, papers, and conference participation followed. He then joined TCS and led work in a mobile security group within digital innovation, combining community research with experience of the corporate world.
Appknox did not begin as a carefully planned startup. Subho was interviewing with other companies when an opportunity prompted him to take a leap. Market timing helped: mobile usage was accelerating as India’s digital economy grew. Yet customers initially valued web testing more than mobile security, so the team sometimes bundled web work at a lower cost to gain access to the mobile applications it wanted to understand and protect.
At the beginning, Subho wrote code, merged pull requests, and handled detailed technical work. As CTO, his productive morning hours shifted toward technical leadership. As CEO, those same hours now go to strategy.
He divides the day into four broad periods. The first is reserved for the work requiring the clearest thinking. The second covers tactical execution and urgent problems. The third is for planning the next day or week, including unfinished work. The fourth is for relationships, conversations with other entrepreneurs, and life outside work.
Today, much of his role involves people, negotiations, external representation, and deciding which strategic levers to pull. A startup with limited resources must be selective about where it tries to outperform larger companies.
Subho is frank that a neat separation between work and life is difficult for a founder. Early in Appknox’s history, when four people served several clients, he worked for two nights without sleep and fainted. That incident made physical limits impossible to ignore.
He now protects at least four to five hours of sleep even when travel or international calls complicate the schedule. He also tries to be fully present: when working, he gives work his attention; on vacation or spending time with others, he avoids notifications unless the company faces a genuine emergency. The aim is not a perfect timetable but deliberate recovery within an irregular founder schedule.
Subho’s first principle for founders is customer obsession. A product has no purpose if the team does not understand the people expected to buy and use it. Listening does not mean implementing every request. It means finding the underlying need, comparing it across customers, and deciding what the product should solve.
Appknox’s early choices illustrate that distinction. Customers asked for web security work, but the company maintained its commitment to mobile security while using adjacent services to learn, build relationships, and survive until the market matured.
Building something meaningful can take years. Appknox had been operating for more than a decade, and Subho emphasizes that resilience is necessary long after launch. At the same time, persistence should not become attachment to a failing tactic.
A useful vision looks beyond today’s implementation. Founders should imagine where the product or company needs to be in one or two years and work backward to the capabilities required now. Within that direction, they should remain agile. If evidence shows an approach is not working, stop dragging it forward, learn from it, and try another path. That can be emotionally difficult because a product feels personal, but fast course correction protects scarce time and resources.
