1a. It's not need subscription.
2b. ArcaBook - http://www.tradearca.com/tools/book/book_info.asp
3c. Data refresh - 3 seconds.
Total orders in the (and below) BID.
Total orders in the (and above) ASK.
Green color - the best BID and ASK order size.
Liquidity indicator BID (high value mean low liquidity and low value mean high liquidity).
Liquidity indicator ASK (high value mean low liquidity and low value mean high liquidity).
SumSize - Liquidity indicator BID (Sum of all BID orders size. High value mean high liquidity and low value mean low liquidity).
SumSize - Liquidity indicator ASK (Sum of all ASK orders size. High value mean high liquidity and low value mean low liquidity).
5e. Change "Text size table " and "Table heigh" to transform to tablets.
2. NYSE Arca Auctions tool gives investors the unique opportunity to view the stocks that are part of the opening, market order, closing and halted auction process in addition to associated indicative match prices and quantities.
2.1 Table orientation.
Indicative Match Price =AuctionPrice
2.2 Publishing Order Imbalances
Beginning at 3:00 p.m. ET and updated real-time thereafter, the Indicative Match Price, the volume to trade at that point, and any order imbalances associated with the Closing Auction, if any, will be published by NYSE Arca in both the ArcaBooksm data feed and on the website. The following information will be published:
Market Imbalance — the imbalance of any remaining buy (sell) MOC orders that are not already matched for execution in the auction.
Total Imbalance Reflects the total net imbalance of MOC, LOC and orders displayed in the ArcaBook.
Matched Volume — The volume already matched for execution at the indicative match price.
Indicative Match Price — The price at which the maximum volume of shares are executable.
Open postions in S&P 500 - https://play.google.com/store/apps/details?id=sp500.sp500&hl=en