(Reuters) - Video-streaming device maker Roku Inc reported quarterly revenue above market expectations on Thursday, thanks to an influx of cord-cutting subscribers dropping their cable packages for streaming services. A pandemic winner, Roku’s aggressive push into original releases on its own app, Roku Channel, and subscriber boosts to the streaming platforms it hosts including Netflix, Prime Video and Disney+ have not only bolstered its device sales, but also its ad income. Roku added 14.3 million active accounts in the year, bringing total active accounts to 51.2 million. Sales of its devices, which connects televisions to streaming services, rose 18% to $178.7 million in the fourth quarter. Platform revenue, which includes ad sales, surged 81% to $471.2 million, beating estimates of $416.07 million. Total net revenue rose 58% to $649.9 million in the fourth quarter, beating analysts’ average estimate of $617.25 million, according to IBES data from Refinitiv. Excluding items, Roku posted a surprise profit of 49 cents per share, while analysts expected a 5 cents loss. For the first quarter, the company expects total revenue between $478 million and