Abbreviation of 'subscription' (サブスクリプション). Refers to services or contracts that provide continued access to content or services for a regular fee (e.g., monthly).
最近は音楽も映画もサブスクで視聴する人が増えた。
Recently, more people watch music and movies via subscriptions.
このアプリはサブスク形式で、月額500円だ。
This app is subscription-based and costs 500 yen per month.
雑誌は紙版を買うよりサブスクで読むことが多い。
I often read magazines via subscription rather than buying the paper version.