Osaka Castle Park is pretty big, beautiful and free. Only entrance to the Osaka castle need to pay.

Soft cheese pancake breakfast, nice. Other options are simple but nice.
软绵绵乳酪Pancake, 好吃不腻。其他早点也不错。

The main shopping street.

Absolutely superb crepe. Sweet Mont Blanc is nice, but pork with mushroom crepe is amazing.
无敌甜品,尤其是五层肉蘑菇Crepe,Mont Blanc 甜点也好吃。

3GB 30 Days sim card for 2800 Yen.

Egg wrapped rice, pretty alright.

Though it is a franchise, the coffee, food and dessert are pretty good.

Totoro shop at Osaka Station, LUCUA 9th floor.

Octopus Takoyaki 350yen, too soft and mushy.

Quiet and clean apartment, 20m walk away from Dotonbori area (pretty far), 10m away from the nearest JR station (good if you hold JR pass).

Data Sim Card at Kansai Airport. A 30 days 3GB sim card can range from 4000 yen to 9000 yen. I pickup at TRE (3GB 30 days) at JAL counter for 4500 yen. Saw another similar package selling for 4000 yen at the vending machine.

PS: Cheaper options are available in town, selling at places like BIC Camera.