I will freely admit to being a bit of a ケチなやつ (kechina yatsu, cheapskate). This is generally not something you should state in public, mostly because both kechi and yatsu are very casual and therefore very 荒い (arai, rough) language. A nicer way to put it would be 節約家 (setsuyakuka, frugal person).
I bring my own lunch to work every day. I use public transport and only take Uber on occasion. Chicago's 公共 交通機関 (kōkyō kōtsū kikan, public transport) isn't quite as impressive as Tokyo's, but it gets the job done. And I borrow books and DVDs from the 公共図書館 (kōkyō toshokan, public library).
But recently I dropped serious cash on a mere アップ (appu, app): I paid $119.99 (¥13,800) for a Japanese-English dictionary on my iPhone. However, it has been worth every penny.