PayPal CEO Dan Schulman praised the progress made by his company to strengthen its position in mobile during 2018, though acknowledged significant challenges lay ahead from existing and new competitors.

“As we look forward to 2019 and beyond, it is … clear that great opportunities and challenges lie ahead,” the executive said in a letter to employees reviewing 2018. “As the world’s economy continues to digitise, our space has never been more attractive to challengers and incumbents.”

In the note, Schulman hailed headway made during the previous 12 months, stating it had: “extended our leadership in mobile,” adding “in a short period of time we have transitioned from being a button on a website to one of the biggest enablers of global commerce.”

During the period the company launched a new mobile app under its core brand and upgraded its Venmo platform, including launching a Venmo debit card to increase acceptance in physical stores.

However, in 2018 Venmo was also in the headlines for hiking instant transfer fees and appointed its third boss in the space of two years.

As of the end of the year PayPal had almost 40 strategic partnerships in place with partners, described by Schulman as some of the most influential names in finance, retail and technology. In 2018, it also acquired a number of companies to enhance its offering, including point of sale terminal provider iZettle.